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Sample records for energy converterby mbe

  1. Fabrication of photovoltaic laser energy converterby MBE

    NASA Technical Reports Server (NTRS)

    Lu, Hamilton; Wang, Scott; Chan, W. S.

    1993-01-01

    A laser-energy converter, fabricated by molecular beam epitaxy (MBE), was developed. This converter is a stack of vertical p-n junctions connected in series by low-resistivity, lattice matched CoSi2 layers to achieve a high conversion efficiency. Special high-temperature electron-beam (e-beam) sources were developed especially for the MBE growth of the junctions and CoSi2 layers. Making use of the small (greater than 1.2 percent) lattice mismatch between CoSi2 and Si layers, high-quality and pinhole-free epilayers were achieved, providing a capability of fabricating all the junctions and connecting layers as a single growth process with one pumpdown. Well-defined multiple p-n junctions connected by CoSi2 layers were accomplished by employing a low growth temperature (greater than 700 C) and a low growth rate (less than 0.5 microns/hour). Producing negligible interdiffusion, the low growth temperature and rate also produced negligible pinholes in the CoSi2 layers. For the first time, a stack of three p-n junctions connected by two 10(exp -5) Ohm-cm CoSi2 layers was achieved, meeting the high conversion efficiency requirement. This process can now be optimized for high growth rate to form a practical converter with 10 p-n junctions in the stack.

  2. Surface Evolution during MBE Growth

    NASA Astrophysics Data System (ADS)

    Orme, C.; Orr, B. G.

    The evolution of surfaces grown using molecular beam epitaxy (MBE) is an interesting scientific issue as well as an important technological concern. In this review article we examine surface evolution during film growth from several different points of view. Experimental, simulational and analytical descriptions of the process are discussed.

  3. Arsenic-induced intensity oscillations in reflection high-energy electron diffraction measurements. [during MBE of GaAs and InAs

    NASA Technical Reports Server (NTRS)

    Lewis, B. F.; Fernandez, R.; Grunthaner, F. J.; Madhukar, A.

    1986-01-01

    A technique of arsenic-induced RHEED intensity oscillations has been used to accurately measure arsenic incorporation rates as a function of substrate temperature during the homoepitaxial growths of both GaAs and InAs by molecular beam epitaxy (MBE). Measurements were made at growth temperatures from 350 to 650 C and at arsenic fluxes of 0.1 to 10.0 monolayer/s. The method measures only the arsenic actually incorporated into the growing film and does not include the arsenic lost in splitting the arsenic tetramers or lost by evaporation from the sample.

  4. A Novel Technique for Detecting Trace Residues of Contamination on GaAs Surfaces before MBE Growth

    NASA Astrophysics Data System (ADS)

    Lee, Jerry; West, Ken; Baldwin, Kirk; Pfeiffer, Loren

    2012-02-01

    To prepare a GaAs substrate for molecular beam epitaxial (MBE) growth, the nominal ˜ 3 nm native oxide is typically thermally desorbed in vacuum. To test the completeness of this desorption, we describe a technique, which combines MBE, thermal desorption, atomic force microscopy (AFM), reflection high-energy electron diffraction (RHEED), and secondary ion mass spectroscopy (SIMS), for detecting trace residues of contamination on (100) GaAs surfaces before MBE growth. At all desorption temperatures in the range 600 C to 665 C, our RHEED measurements show that the native oxide is largely desorbed within 2 min. However, the SIMS and AFM data indicate that a residue of sub-monolayer oxide invariably remains on the GaAs (100) surface, and tenaciously resists all further attempts at its removal by thermal desorption. Since thermal desorption of the native oxide has long been the standard technique before MBE growth, we suggest that all MBE growth of GaAs heterostructures has been through a partial monolayer of native oxide. We believe that this is the likely reason for the failure of high quality attempts at MBE growth of GaAs after lithographic patterning on a previously grown MBE structure.

  5. van der Waals Heterostructures Grown by MBE

    NASA Astrophysics Data System (ADS)

    Hinkle, Christopher

    In this work, we demonstrate the high-quality MBE heterostructure growth of various layered 2D materials by van der Waals epitaxy (VDWE). The coupling of different types of van der Waals materials including transition metal dichalcogenide thin films (e.g., WSe2, WTe2, HfSe2) , insulating hexagonal boron nitride (h-BN), and topological insulators (e.g., Bi2Se3) allows for the fabrication of novel electronic devices that take advantage of unique quantum confinement and spin-based characteristics. The relaxed lattice-matching criteria of van der Waals epitaxy has allowed for high-quality heterostructure growth with atomically abrupt interfaces, allowing us to couple these materials based primarily on their band alignment and electronic properties. We will discuss the impact of sample preparation, surface reactivity, and lattice mismatch of various substrates (sapphire, graphene, TMDs, Bi2Se3) on the growth mode and quality of the films and will discuss our studies of substrate temperature and flux rates on the resultant growth and grain size. Structural and chemical characterization was conducted via reflection high energy electron diffraction (RHEED, X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning tunneling microscopy/spectroscopy (STM/S), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), and Raman spectroscopy. Experimentally determined band alignments have been determined and compared with first-principles calculations allowing the design of novel low-power logic and magnetic memory devices. Initial results from the electrical characterization of these grown thin films and some simple devices will also be presented. These VDWE grown layered 2D materials show significant potential for fabricating novel heterostructures with tunable band alignments and magnetic properties for a variety of nanoelectronic and optoelectronic applications.

  6. MBE HgCdTe heterostructure detectors

    NASA Technical Reports Server (NTRS)

    Schulman, Joel N.; Wu, Owen K.

    1990-01-01

    HgCdTe has been the mainstay for medium (3 to 5 micron) and long (10 to 14 micron) wavelength infrared detectors in recent years. Conventional growth and processing techniques are continuing to improve the material. However, the additional ability to tailor composition and placement of doped layers on the tens of angstroms scale using molecular beam epitaxy (MBE) provides the opportunity for new device physics and concepts to be utilized. MBE-based device structures to be discussed here can be grouped into two categories: tailored conventional structures and quantum structures. The tailored conventional structures are improvements on familiar devices, but make use of the ability to create layers of varying composition, and thus band gap, at will. The heterostructure junction can be positioned independently of doping p-n junctions. This allows the small band gap region in which the absorption occurs to be separated from a larger band gap region in which the electric field is large and where unwanted tunneling can occur. Data from hybrid MBE/liquid phase epitaxy (LPE)/bulk structures are given. Quantum structures include the HgTe-CdTe superlattice, in which the band gap and transport can be controlled by alternating thin layers (tens of angstroms thick) of HgTe and CdTe. The superlattice has been shown to exhibit behavior which is non-alloy like, including very high hole mobilities, two-dimensional structure in the absorption coefficient, resonant tunneling, and anisotropic transport.

  7. 15. VIEW TO SOUTHWEST; EAST BACK MBE BUILDING, THIRD AND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    15. VIEW TO SOUTHWEST; EAST BACK MBE BUILDING, THIRD AND SECOND FLOORS; GASOLINE PUMPS CENTER (Dobson) - Los Angeles Union Passenger Terminal, Mail, Baggage, & Express Building, 800 North Alameda Street, Los Angeles, Los Angeles County, CA

  8. MBE growth and characteristics of antimonide-based quantum dots

    NASA Astrophysics Data System (ADS)

    Wang, Xue

    Semiconductor quantum dots (QDs) are an important class of low dimensional materials for optoelectronic applications since they offer the possibility of a three-dimensional carrier confinement. Among III-V semiconductor material systems, antimony-based QDs hold the promise for the realization of low threshold room-temperature mid-infrared lasers because of the low band gap energy (0.17 eV at 300K) of InSb and the large lattice mismatch between InSb and GaSb. The fabrication of InSb/GaSb self-assembled QDs for optoelectronic applications by Molecular Beam Epitaxy (MBE) is ventured in this dissertation. Here both uncapped and capped self-assembled InSb QDs are fabricated by MBE on nominal GaSb (100)+/-0.1°and GaSb (100)+/-6°. The growth conditions are optimized to obtain QDs with both high density and good uniformity. The influence of growth parameters i.e., substrate temperature, nominally deposited thickness, annealing time and substrate orientation on QD size, uniformity and distribution, are systematically studied. The structural and optical properties of these QDs are characterized using in-situ Reflection High-energy Electron Diffraction (RHEED), and ex-situ Atomic Force Microscopy (AFM) and Photo-Luminescence (PL) measurements. Confined energy levels in the strained InSb/GaSb QD system are estimated theoretically and compared with the experimental results. Three-dimensional uncapped InSb QDs were successfully grown on GaSb (100) substrates at a density of 2.8x109/cm2 by MBE via the Stranski-Krastanov mode of self-organization. The two-dimensional to three-dimensional transition in this mode releases the strain arising from the mis-match between the substrate and the epilayer. The average base side length of the resulting QDs is 100+/-24 nm and the height is 4.9+/-1.6 nm. The best size uniformity, with standard deviations of 23% for base length and 48% for height was obtained under the optimized growth conditions of 3.9ML material deposition, a growth

  9. Synchrotron x-ray photoconductor detector arrays made on MBE grown CdTe

    SciTech Connect

    Yoo, S.S.; Montano, P.A. |; Rodricks, B.; Sivananthan, S.; Faurie, J.P.

    1996-08-01

    We have been fabricating x-ray photoconductor linear array detectors using molecular beam epitaxially (MBE) grown (111)B undoped CdTe layers on (100) Si substrates. A novel technique was developed to remove the Si and to mount the fragile MBE grown CdTe layers onto insulating ceramic substrates. 256 channel linear photoconductor array devices were fabricated on the resulting CdTe layers. The resistivity of MBE (111)B CdTe was high (> 10{sup 8} {Omega}cm) enough to utilize the material for low energy (8 to 25 keV) x-ray detectors. The stability of the detectors are satisfactory, and they were tested at room temperature routinely for over a year. The performance of the photoconductor was greatly improved when the detector was cooled to 230K. Due to its reduced dark current at low temperatures, the dynamic range of the detector response increased to nearly four decades at 230K. 29 refs., 8 figs.

  10. Gold coverage and faceting of MBE grown silicon nanowires

    NASA Astrophysics Data System (ADS)

    David, Thomas; Roussel, Luc; Neisius, Thomas; Cabie, Martiane; Gailhanou, Marc; Alfonso, Claude

    2013-11-01

    In this paper, we investigate the faceting of molecular beam epitaxy (MBE) grown nanowires and the post-growth repartition of the gold used as catalyst. Electron microscopy analysis are performed using Scanning Transmission Electron Microscopy - High Angle Annular Dark Field (STEM-HAADF), electron tomography, and Energy-dispersive X-ray spectroscopy (EDS) to collect complementary information. The nanowires present very little to no faceting at the very top, very close to the catalyst, suggesting the nanowires grow with a quasi-circular section at the early stages of growth. The nanowires are then found to have an hexagonal and/or dodecagonal section and present a finer ‘saw-tooth’ faceting on the main faces. We find gold clusters spread on the surfaces of the nanowires, but we could not observe any gold inside the nanowires. Furthermore, the gold coverage is uneven on the different facets of the nanowire. The creation of these facets and the gold coverage are two linked phenomena balancing each other.

  11. STM and MBE: one of the best combinations

    NASA Astrophysics Data System (ADS)

    Jia, Jin-Feng; Ma, Xucun; Chen, Xi; Sakurai, T.; Xue, Qi-Kun

    2011-11-01

    It has been 30 years since the scanning tunnelling microscope (STM) was invented by G Binnig and H Rohrer. Rapid developments have made STM increasingly powerful as an extremely versatile technique for many disciplines in condensed matter physics, chemistry, biology and other areas. As a state-of-the-art growth method, molecular beam epitaxy (MBE) is a gifted technique for epitaxial growth with atomic-level control. In this paper, by giving several examples, we will show that an STM-MBE combined system is more powerful and unique for studies on low-dimensional and new functional materials.

  12. Let the Questions Be Your Guide: MBE as Interdisciplinary Science

    ERIC Educational Resources Information Center

    Rose, L. Todd; Daley, Samantha G.; Rose, David H.

    2011-01-01

    From its inception, the field of Mind, Brain, and Education (MBE) has been conceived as an interdisciplinary science, and with good reason: The phenomena the field aims to understand often arise from interactions among multiple factors, span levels of analysis, and are context dependent. In this article, we argue that to reach its potential as an…

  13. 52. VIEW TO EAST; SOUTH END OF MBE BUILDING, SECOND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    52. VIEW TO EAST; SOUTH END OF MBE BUILDING, SECOND FLOOR; HIGHLY ALTERED INTERIOR OFFICE SPACE, FORMERLY REGIONAL OFFICES OF REA (Andersen) - Los Angeles Union Passenger Terminal, Mail, Baggage, & Express Building, 800 North Alameda Street, Los Angeles, Los Angeles County, CA

  14. Effects of incident short wavelength (UV) light on the morphology of MBE grown GaAs

    NASA Astrophysics Data System (ADS)

    Beaton, Daniel A.; Sanders, Charlotte; Alberi, Kirstin

    2014-03-01

    The exploration of novel semiconductor materials increasingly relies on growth techniques that operate far from equilibrium in order to overcome thermodynamic limitations to synthesis. As one example, low temperature molecular beam epitaxy (MBE) offers a pathway to enhance substitutional dopant incorporation over surface segregation but adatom mobility suffers as a consequence and leads to higher concentrations of lattice defects. We explore the use of external stimuli, namely incident UV light, as a means to influence adatom kinetics; UV light is absorbed in the first few atomic layers of the as-growing epitaxial film and the effects of the incident radiation predominantly effect only the surface adatoms. GaAs homoepitaxy by MBE is studied as a model case as a function of illumination conditions under broadband Xe and KrF excimer laser irradiation. In-situ reflective high energy electron diffraction analysis paired with ex-situ atomic force microscopy measurements yields insight into the effects of photon irradiation on surface adatom mobility, morphology and smoothing processes. This work was supported by the DOE Office of Science, Basic Energy Sciences under contract DE-AC36-08GO28308.

  15. Unraveling the electron pairing mechanism of FeSe by MBE and STM

    NASA Astrophysics Data System (ADS)

    Song, Canli

    Studies of high-transition-temperature superconductivity usually suffer from various imperfections in materials. Here we apply the state-of-the-art molecular beam epitaxy (MBE) to prepare controllably high-quality FeSe films on various substrates, and explore their superconducting properties using cryogenic scanning tunneling microscope. Single impurities, twin boundaries as well as strain are found in the MBE-grown FeSe films on graphene, and invariably suppress the superconductivity. Meanwhile, electronic nematicity and signatures of a bosonic mode, whose energy also decreases with strain, were identified. More significantly, we observed two disconnected superconducting domes at alkali-metal potassium (K)-dosed FeSe surface, stepping towards the mechanistic understanding of superconductivity in FeSe-derived superconductors. Our results are clarifying the secret of high-Tc superconductivity in FeSe-related superconductors, and by implications, in other unconventional superconductors, and guiding how to enhance Tc by interface engineering. This work was nancially supported by National Science Foundation and Ministry of Science and Technology of China.

  16. Superconducting proximity effect in MBE grown Nb-InAs junctions

    NASA Astrophysics Data System (ADS)

    Kan, Carolyn; Xue, Chi; Law, Stephanie; Eckstein, James

    2013-03-01

    Several proposals for the realization of Majorana fermions rely on excellent quality proximity coupling between a superconductor and a high-mobility semiconductor. We examine the long-range proximity coupling between MBE-grown InAs and in situ grown superconducting overlayers by fabricating transport devices, and investigate the effect of substrate choice and growth conditions on the quality of the MBE InAs. GaAs is commonly available as a high quality insulating substrate. Overcoming its lattice mismatch with InAs using GaSb and AlSb layers results in locally smooth terraced surfaces, but global spiral dislocation structures also appear and have a negative impact on the InAs mobility. Growing InAs on homoepitaxial GaSb results in improved morphology and increases the mean free path. We compare the proximity effect in devices made both ways. This material is based upon work supported by the U.S. Department of Energy, Division of Materials Sciences under Award No. DE-FG02 07ER46453, through the Frederick Seitz Materials Research Laboratory at the University of Illinois at Urbana-Champaign.

  17. Preface of the 18th International Conference on Molecular Beam Epitaxy (MBE 2014)

    NASA Astrophysics Data System (ADS)

    Brown, April S.; Ptak, Aaron J.

    2015-09-01

    The first International Conference on Molecular Beam Epitaxy (IC-MBE) was held in Paris in 1978, chaired by Alfred Y. Cho. Every other year since, with the exception of a four-year break after the initial meeting, the IC-MBE has been held in European, Asian, and North American venues. The 18th and latest IC-MBE was held in Flagstaff, Arizona, USA, September 7-12, 2014, and was chaired by Yong-Hang Zhang (Arizona State University). MBE is an advanced crystal growth method that benefits areas from the study of fundamental physics, all the way through the production of devices used in countless fields. IC-MBE brings together researchers from all over the world, and is the premier forum for scientific and technological exchange among researchers investigating all types of materials growth using the MBE technique.

  18. Millimeterwave and digital applications of InP-based MBE grown HEMTs and HBTs

    NASA Astrophysics Data System (ADS)

    Greiling, Paul

    1997-05-01

    Microwave and millimeterwave devices grown by MBE have significantly advanced the state of the art for RF device performance with respect to noise figure, power output, power added efficiency and extended the clock frequency of digital circuits into the millimeterwave regime. Ober the last 10-15 years, military systems have greatly benefited from the superior performance of MBE grown devices. In order to have a similar impact on the commercial marketplace, MBE growers will have to focus their efforts on a different set of performance criteria; i.e. cost, uniformity and reproducibility. This paper discusses outstanding performance achieved by MBE grown devices and outlines the criteria for commercial applications.

  19. Solid source MBE growth of quantum cascade lasers

    NASA Astrophysics Data System (ADS)

    Liu, Feng-Qi; Li, Lu; Wang, Lijun; Liu, Junqi; Zhang, Wei; Zhang, Quande; Liu, Wanfeng; Lu, Quanyong; Wang, Zhanguo

    2009-11-01

    High material quality is the basis of quantum cascade lasers (QCLs). Here we report the solid source molecular beam epitaxy (MBE) growth details of realizing high quality of InGaAs/InAlAs QCL structures. Accurate control of material compositions, layer thickness, doping profile, and interface smoothness can be realized by optimizing the growth conditions. Double crystal x-ray diffraction discloses that our grown QCL structures possess excellent periodicity and sharp interfaces. High quality laser wafers are grown in a single epitaxial run. Room temperature continuous-wave (cw) operation of QCLs is demonstrated.

  20. MBE grown high-quality Gd 2O 3/Si(1 1 1) hetero-structure

    NASA Astrophysics Data System (ADS)

    Lin, T. D.; Hang, M. C.; Hsu, C. H.; Kwo, J.; Hong, M.

    2007-04-01

    A nearly lattice-matched Gd 2O 3/Si(1 1 1) hetero-epitaxy was demonstrated using molecular beam epitaxy (MBE). Detailed structural studies find that the nano thick Gd 2O 3 films have a cubic phase with a very uniform thickness, an excellent crystallinity and atomically sharp interfaces. These features are characterized by the bright, streaky reconstructed reflection high-energy electron diffraction (RHEED) patterns at the initial oxide growth, the pronounced interference fringes in the X-ray reflectivity curve as well as in the crystal truncation rod around the substrate diffraction peaks using the high-resolution X-ray diffraction. The (1 1 1) axis of the thin oxide is oriented parallel to the substrate (1 1 1) normal with a 60° in-plane symmetry rotation.

  1. MBE monolayer growth control by in-situ electron microscopy

    NASA Astrophysics Data System (ADS)

    Inoue, N.

    1991-05-01

    A molecular beam epitaxy/scanning reflection electron microscope/scanning electron microscope (MBE-SREM-SEM) hybrid system is developed as an in-situ observation technique for study and control of growth of GaAs and AlGaAs. The resolution is 50 nm for SREM and 30 nm for SEM at 10 s/frame observation rate. The highest observation rate is 1 s/frame for SREM and 1/60 s/frame for SEM. Three applications are established: The observation of quick, transient growth processes to clarify the growth mechanism, the measurement of material properties under actual growth conditions to understand and control growth, and growth control by in-process monitoring, in which a micron scale lateral growth of Ga/Al monolayer is developed.

  2. MBE growth of VCSELs for high volume applications

    NASA Astrophysics Data System (ADS)

    Jäger, Roland; Riedl, Michael C.

    2011-05-01

    Mass market applications like laser computer mouse or optical data transmission based on vertical-cavity surface-emitting laser (VCSEL) chips need a high over all yield including epitaxy, processing, dicing, mounting and testing. One yield limitation for VCSEL structures is the emission wavelength variation of the substrate surface area leading to the fraction on laser chips which are below or above the specification limits. For most 850 nm VCSEL products a resonator wavelength variation of ±2 nm is common. This represents an average resonator thickness variation of much less than 1% which is quite challenging to be fulfilled on the entire processed wafer surface area. A high over all yield is demonstrated on MBE grown VCSEL structures.

  3. MBE-Grown CdTe Layers on GaAs with In-assisted Thermal Deoxidation

    NASA Astrophysics Data System (ADS)

    Arı, Ozan; Bilgilisoy, Elif; Ozceri, Elif; Selamet, Yusuf

    2016-10-01

    Molecular beam epitaxy (MBE) growth of thin (˜2 μm) CdTe layers characterized by high crystal quality and low defect density on lattice mismatched substrates, such as GaAs and Si, has thus far been difficult to achieve. In this work, we report the effects of in situ thermal deoxidation under In and As4 overpressure prior to the CdTe growth on epiready GaAs(211)B wafers, aiming to enhance CdTe crystal quality. Thermally deoxidized GaAs samples were analyzed using in situ reflection high energy electron diffraction, along with ex situ x-ray photo-electron spectroscopy (XPS) and atomic force microscopy. MBE-grown CdTe layers were characterized using x-ray diffraction (XRD) and Everson-type wet chemical defect decoration etching. We found that In-assisted desorption allowed for easier surface preparation and resulted in a smoother surface compared to As-assisted surface preparation. By applying In-assisted thermal deoxidation to GaAs substrates prior to the CdTe growth, we have obtained single crystal CdTe films with a CdTe(422) XRD rocking curve with a full-width half-maximum value of 130.8 arc-s and etch pit density of 4 × 106 cm-2 for 2.54 μm thickness. We confirmed, by XPS analysis, no In contamination on the thermally deoxidized surface.

  4. Investigation of Substrate Effects on Interface Strain and Defect Generation in MBE-Grown HgCdTe

    NASA Astrophysics Data System (ADS)

    Gu, R.; Lei, W.; Antoszewski, J.; Faraone, L.

    2016-09-01

    Si, Ge, and GaAs have been extensively investigated as alternative substrates for molecular-beam epitaxy (MBE) growth of HgCdTe and, at present, are widely used for HgCdTe-based infrared focal-plane arrays. However, the problem of high dislocation density in HgCdTe layers grown on these lattice-mismatched substrates has yet to be resolved. In this work, we investigated another alternative substrate, GaSb, which has a significantly smaller lattice mismatch with HgCdTe in comparison with Si, Ge, and GaAs, and is readily available as large-area, epiready wafers at much lower cost in comparison with lattice-matched CdZnTe substrates. The resultant stress due to lattice and thermal mismatch between the HgCdTe epilayer and various substrates has been calculated in this work using the elasticity matrix, and the corresponding stress distribution simulated using ANSYS. The simulated structures were matched by experimental samples involving MBE growth of HgCdTe on GaAs, GaSb, and CdZnTe substrates, and were characterized via reflection high-energy electron diffraction and x-ray diffraction analysis, followed by etch pit density (EPD) analysis. In comparison with other alternative substrates, GaSb is shown to have lower interface stress and lower EPD, rendering it an interesting and promising alternative substrate material for HgCdTe epitaxy.

  5. Surface Properties of SiC Layer Grown by Molecular Beam Epitaxy (MBE) with Helicon Sputtering Molecular Beam Source

    NASA Astrophysics Data System (ADS)

    Kakuta, Akira; Moronuki, Nobuyuki; Furukawa, Yuji

    Although there have been some attempts to produce a monocrystalline silicon carbide (SiC) flat surface, the surface properties, such as surface roughness, have not satisfied the required specifications. In this study, we apply a helicon sputtering device to molecular beam epitaxy (MBE) to improve those properties. The helicon sputtering device was used as a molecular beam source for generating a Si molecular beam, where the electric field caused by the helicon coil supplied energy to the sputtered Si molecules. The amount of energy was controlled by the electric power applied to the coil. High-purity acetylene gas was used as the carbon (C) molecular beam source. The substrate was a monocrystalline (111) Si wafer. With the increase of the electric power, that is, the supply of high energy to molecules, the roughness of the surface was improved. A uniform mirror surface of monocrystalline SiC was produced over the entire substrate with a roughness of 1nm (Ra) order.

  6. MBE growth of topological insulator Bi2Se3 and Bi2Te3 films

    NASA Astrophysics Data System (ADS)

    Zhang, Tong; Levy, Niv; Song, Young Jae; Chae, Jungseok; Stroscio, Joseph A.

    2011-03-01

    Three-dimensional (3D) topological insulators are a new state of quantum matter with a band gap in bulk but gapless states on the surface. The surface states with spin helicity can be the host of many striking quantum phenomena. In this work, we use ultrahigh vacuum molecular beam epitaxy to grow atomically flat topological insulator (TI) Bi2Se3 and Bi2Te3 films. High quality TI films were obtained using epitaxial graphene on SiC as a substrate for TI growth. The growth dynamics was characterized by real time reflection high-energy electron diffraction (RHEED). The growth condition was optimized by adjusting for proper flux rate and substrate temperature while monitoring the RHEED patterns. In situ Auger spectroscopy and scanning tunneling microscopy (STM) measurements at 5K are used to study the as-grown films for their stoichiometry and defect density. We expect these MBE grown samples will provide a good candidate for studying the topological surface states and related phenomena, which will be studied using scanning tunneling spectroscopy at millikelvin temperatures

  7. Accelerator research on MBE-4, an experimental multi-beam induction linac

    SciTech Connect

    Meuth, H.; Fessenden, T.J.; Keefe, D.; Warwick, A.I.

    1988-06-01

    The multiple beam accelerator MBE-4 is a device for research toward a heavy ion driver for inertial confinement fusion, based on the induction linac concept. Its main goal is proof of the principle of current amplification by acceleration and controlled self-similar beam pulse compression. Into the 16-m long device four beams, each with an initial current of 10 mA are injected from a Marx-driven diode at 200 keV. The current amplification is up to nine-fold, with a final beam energy of about 800 keV in the middle of the bunch. Now that all the apparatus' accelerator sections have been completed, installed and aligned, and its unaccelerated transport properties have been studied, our experimental research has reached the crucial phase of implementing appropriate accelerator schedules that approximate self-similar current-pulse compression. These schedules are established through a close interplay of computations using a one-dimensional simulation code and a manual empirical tuning procedure. In a first approach, with a rather vigorous schedule that uses most of the accelerator modules to their voltage limits, we have determined the limits of our capability for controlled pulse compression, mainly due to waveform shaping of the driving pulse-forming networks. We shall report on these results. In the future, we will also aim for gentler schedules that would model more closely an inertial confinement fusion scenario. 8 refs., 11 figs., 1 tab.

  8. IMPORTANCE OF IN SITU MONITORS IN THE PREPARATION OF LAYERED OXIDE HETEROSTRUCTURES BY REACTIVE MBE.

    SciTech Connect

    Schlom, Darrell G.; Haeni, J. H.; Theis, C. D.; Tian, W.; Pan, X. Q.; Brown, G. W.; Hawley, M. E.

    2001-01-01

    Using a variety of in situ monitors and when possible adsorption-controlled growth conditions, layered oxide heterostructures including new compounds and metastable superlattices have been grown by reactive molecular beam epitaxy (MBE). The heteroepitaxial layers grown include Bi{sub 4}Ti{sub 3}O{sub 12}-SrTiO{sub 3} and Bi{sub 4}Ti{sub 3}O{sub 12}-PbTiO{sub 3} Aurivillius phases, Sr{sub n+1}Ti{sub n}O{sub 3n+1} Ruddlesden-Popper phases, and metastable PbTiO{sub 3}/SrTiO{sub 3} and BaTiO{sub 3}/SrTiO{sub 3} superlattices. Accurate composition control is key to the controlled growth of such structures, and to this end combinations of reflection high-energy electron diffraction (RHEED), atomic absorption spectroscopy (AA), a quartz crystal microbalance (QCM), and adsorption-controlled growth conditions were employed during growth. The structural perfection of the films has been investigated using in situ RHEED, four-circle x-ray diffraction, atomic force microscopy (AFM), and high-resolution transmission electron microscopy (TEM).

  9. Methods for the doping of silicon layers in growth by sublimation MBE

    SciTech Connect

    Shengurov, V. G.; Svetlov, S. P. Chalkov, V. Yu.; Shengurov, D. V.; Denisov, S. A.

    2006-02-15

    Epitaxial layers doped with various impurities were grown by sublimation MBE on Si (100) substrates. Doping with phosphorus was controlled at electron densities ranging from 2x10{sup 13} to 10{sup 19} cm{sup -3}. A high dopant concentration of {approx}10{sup 20} cm{sup -3} was obtained from the evaporation of partly molten Si sources. It shown that the type and concentration of an impurity in the sublimation MBE process can be controlled by the fabrication of multilayer p{sup +}-n{sup +} structures.

  10. Effect of GaAs native oxide upon the surface morphology during GaAs MBE growth

    NASA Astrophysics Data System (ADS)

    Ageev, O. A.; Solodovnik, M. S.; Balakirev, S. V.; Mikhaylin, I. A.; Eremenko, M. M.

    2016-08-01

    The GaAs native oxide effect upon the surface morphology of the GaAs epitaxial layer was studied with taking into account the main growth parameters of MBE technology: substrate temperature, effective As4/Ga flux ratio and growth rate. The MBE modes of atomically smooth and rough surfaces and surfaces with Ga droplet array formation were determined. The possibility of the obtaining of GaAs nanowires via GaAs native oxide layer was shown.

  11. Influence of Growth Parameters and Annealing on Properties of MBE Grown GaAsSbN SQWs

    NASA Technical Reports Server (NTRS)

    Wu, Liangjin; Iyer, Shanthi; Nunna, Kalyan; Bharatan, Sudhakar; Li, Jia; Collis, Ward J.

    2005-01-01

    In this paper we report the growth of GaAsSbN/GaAs single quantum well (SQW) heterostructures by molecular beam epitaxy (MBE) and their properties. A systematic study has been carried out to determine the effect of growth conditions, such as the source shutter opening sequence and substrate temperature, on the structural and optical properties of the layers. The substrate temperatures in the range of 450-470 C were found to be optimal. Simultaneous opening of the source shutters (SS) resulted in N incorporation almost independent of substrate temperature and Sb incorporation higher at lower substrate temperatures. The effects of ex-situ annealing in nitrogen ambient and in-situ annealing under As ovepressure on the optical properties of the layers have also been investigated. A significant increase in photoluminescence (PL) intensity with reduced full width at half maxima (FWHM) in conjunction with a blue shift in the emission energy was observed on 10 annealing the samples. In in-situ annealed samples, the PL line shapes were more symmetric and the temperature dependence of the PL peak energy indicated significant decrease in the exciton localization energy as exhibited by a less pronounced S-shaped curve. The inverted S-shaped curve observed in the temperature dependence of PL FWHM is also discussed. 1.61 micrometer emission with FWHM of 25 meV at 20K has been obtained in in-situ annealed GaAsSbN/GaAs SQW grown at 470 C by SS.

  12. Large format MBE HgCdTe on silicon detector development for astronomy

    NASA Astrophysics Data System (ADS)

    Hanold, Brandon J.; Figer, Donald F.; Lee, Joong; Kolb, Kimberly; Marcuson, Iain; Corrales, Elizabeth; Getty, Jonathan; Mears, Lynn

    2015-08-01

    The Center for Detectors at Rochester Institute of Technology and Raytheon Vision Systems (RVS) are leveraging RVS capabilities to produce large format, short-wave infrared HgCdTe focal plane arrays on silicon (Si) substrate wafers. Molecular beam epitaxial (MBE) grown HgCdTe on Si can reduce detector fabrication costs dramatically, while keeping performance competitive with HgCdTe grown on CdZnTe. Reduction in detector costs will alleviate a dominant expense for observational astrophysics telescopes. This paper presents the characterization of 2.5μm cutoff MBE HgCdTe/Si detectors including pre- and post-thinning performance. Detector characteristics presented include dark current, read noise, spectral response, persistence, linearity, crosstalk probability, and analysis of material defects.

  13. Growth of III-V films by control of MBE growth front stoichiometry

    NASA Technical Reports Server (NTRS)

    Grunthaner, Frank J. (Inventor); Liu, John K. (Inventor); Hancock, Bruce R. (Inventor)

    1992-01-01

    For the growth of strain-layer materials and high quality single and multiple quantum wells, the instantaneous control of growth front stoichiometry is critical. The process of the invention adjusts the offset or phase of molecular beam epitaxy (MBE) control shutters to program the instantaneous arrival or flux rate of In and As4 reactants to grow InAs. The interrupted growth of first In, then As4, is also a key feature.

  14. New MBE buffer for micron- and quarter-micron-gateGaAs MESFETs

    NASA Technical Reports Server (NTRS)

    1988-01-01

    A new buffer layer has been developed that eliminates backgating in GaAs MESFETs and substantially reduces short-channel effects in GaAs MESFETs with 0.27-micron-long gates. The new buffer is grown by molecular beam epitaxy (MBE) at a substrate temperature of 200 C using Ga and As sub 4 beam fluxes. The buffer is crystalline, highly resistive, optically inactive, and can be overgrown with high quality GaAs. GaAs MESFETs with a gate length of 0.27 microns that incorporate the new buffer show improved dc and RF properties in comparison with a similar MESFET with a thin undoped GaAs buffer. To demonstrate the backgating performance improvement afforded by the new buffer, MESFETs were fabricated using a number of different buffer layers and structures. A schematic cross section of the MESFET structure used in this study is shown. The measured gate length, gate width, and source-drain spacing of this device are 2,98, and 5.5 microns, respectively. An ohmic contact, isolated from the MESFET by mesa etching, served as the sidegate. The MESFETs were fabricated in MBE n-GaAs layers grown on the new buffer and also in MBE n-GaAs layers grown on buffer layers of undoped GaAs, AlGaAs, and GaAs/AlGaAs superlattices. All the buffer layers were grown by MBE and are 2 microns thick. The active layer is doped to approximately 2 x 10 to the 17th/cu cm with silicon and is 0.3 microns thick.

  15. Static and dynamic magnetic property of MBE-grown Co2FeAl films

    NASA Astrophysics Data System (ADS)

    Qiao, Shuang; Nie, Shuaihua; Huo, Yan; Zhao, Jianhua; Wu, Yizheng; Zhang, Xinhui

    2014-08-01

    In this work, the static and dynamic magnetic properties of Co2FeAl films grown by molecular beam epitaxy (MBE) were studied by employing the magneto-optical Kerr rotation and ferromagnetic resonance (FMR) measurements. The growth temperature dependent magnetocrystalline anisotropy of MBE-grown Co2FeAl films were first investigated by employing the rotating magneto-optical Kerr effect. Then the magnetization dynamics and Gilbert damping property for high quality Co2FeAl films were investigated in detail by combining both the FMR and time-resolved magneto-optical Kerr rotation techniques. The apparent damping parameter was found to show strong dependence on the strength of the applied magnetic field at low-field regime, but decrease drastically with increasing magnetic field and eventually become a constant value of 0.004 at high-field regime. The inhomogeneity of magnetocrystalline anisotropy and two-magnon scattering are suggested to be responsible for the observed abnormal damping properties observed especially at low field regime. The intrinsic damping parameter of 0.004 is deduced for our highly-ordered Co2FeAl film. Our results provide essential information for highly-ordered MBE-grown Co2FeA film and its possible application in spintronic devices.

  16. Recent progress in MBE grown HgCdTe materials and devices at UWA

    NASA Astrophysics Data System (ADS)

    Gu, R.; Lei, W.; Antoszewski, J.; Madni, I.; Umana-Menbreno, G.; Faraone, L.

    2016-05-01

    HgCdTe has dominated the high performance end of the IR detector market for decades. At present, the fabrication costs of HgCdTe based advanced infrared devices is relatively high, due to the low yield associated with lattice matched CdZnTe substrates and a complicated cooling system. One approach to ease this problem is to use a cost effective alternative substrate, such as Si or GaAs. Recently, GaSb has emerged as a new alternative with better lattice matching. In addition, implementation of MBE-grown unipolar n-type/barrier/n-type detector structures in the HgCdTe material system has been recently proposed and studied intensively to enhance the detector operating temperature. The unipolar nBn photodetector structure can be used to substantially reduce dark current and noise without impeding photocurrent flow. In this paper, recent progress in MBE growth of HgCdTe infrared material at the University of Western Australia (UWA) is reported, including MBE growth of HgCdTe on GaSb alternative substrates and growth of HgCdTe nBn structures.

  17. Preliminary report on the MBE-4, an experimental multiple-beam induction linear accelerator for heavy ions

    SciTech Connect

    Warwick, A.I.; Gough, D.E.; Meuth, H.

    1988-11-01

    A small-scale experimental accelerator called MBE-4 has been constructed to demonstrate the principle of a current-amplifying induction linac for multiple beams of heavy ions. Four beams of Cs{sup 1+}, initially at 200 keV and each with a current of 10 mA have been accelerated and amplified to a kinetic energy of 700 keV and currents of 90 mA apiece. Transverse focusing is achieved by means of electrostatic quadrupoles; longitudinally the current is amplified and the beam bunch is held together against the space charge forces by special time-dependent accelerating fields. We report on the methods developed for designing and implementing the accelerating pulses and on measurements of the transverse and longitudinal emittance of the accelerated beams. Current fluctuations and the longitudinal emittance are initially almost zero and increase as acceleration errors are accumulated. We discuss the final longitudinal emittance and the current fluctuations in the experiment in terms of their acceptability for a large heavy-ion-fusion driver. 17 refs., 23 figs., 3 tabs.

  18. Modified MBE hardware and techniques and role of gallium purity for attainment of two dimensional electron gas mobility >35×106 cm2/V s in AlGaAs/GaAs quantum wells grown by MBE

    NASA Astrophysics Data System (ADS)

    Gardner, Geoffrey C.; Fallahi, Saeed; Watson, John D.; Manfra, Michael J.

    2016-05-01

    We provide evidence that gallium purity is the primary impediment to attainment of ultra-high mobility in a two-dimensional electron gas (2DEG) in AlGaAs/GaAs heterostructures grown by molecular beam epitaxy (MBE). The purity of gallium can be enhanced dramatically by in-situ high temperature outgassing within an operating MBE. Based on analysis of data from an initial growth campaign in a new MBE system and modifications employed for a 2nd growth campaign, we have produced 2DEGs with low temperature mobility μ in excess of 35×106 cm2/V s at density n=3.0×1011/cm2 and μ=18×106 cm2/V s at n=1.1×1011/cm2. Our 2nd campaign data indicate that gallium purity remains the factor currently limiting μ<40×106 cm2/V s. We describe strategies to overcome this limitation.

  19. Low-power optically addressed spatial light modulators using MBE-grown III-V structures

    NASA Astrophysics Data System (ADS)

    Maserjian, Joseph L.; Larsson, Anders G.

    1991-12-01

    Device approaches are investigated for O-SLMs based on MBE engineered III-V materials and structures. Strong photo-optic effects can be achieved in periodically (delta) -doped multiple quantum well (MQW) structures. The doping-defined barriers serve to separate and delay recombination of the photo-generated electron-hole pairs. One can use this photo-effect to change the internal field across the MQWs giving rise to quantum-confined Stark shift. Alternately, the photo-generated electrons can be used to occupy the quantum wells, which in turn causes exciton quenching and a shift of the absorption edge. Recent work has shown that both of these predicted photo-optic effects can indeed be achieved in such MBE engineered structures. However, these enhanced effects are still insufficient for high contrast modulation with only single or double pass absorption through active layers of practical thickness. We use the asymmetric Fabry-Perot cavity approach which permits extinction of light due to interference of light reflected from the front and back surfaces of the cavity. Modulation of the absorption in the active cavity layers unbalances the cavity and 'turns on' the reflected output signal, thereby allowing large contrast ratios. This approach is realized with an all-MBE- grown structure consisting of a GaAs/AlAs quarter-wave stack reflector grown over the GaAs substrate as the high reflectance mirror (approximately equals 0.98) and the GaAs surface as the low reflectance mirror (approximately equals 0.3). We use for our active cavities InGaAs/GaAs MQWs separated by npn (delta) -doped GaAs barriers to achieve sensitive photo-optic effect due to exciton quenching. High contrast modulation (> 60:1) is achieved with the Fabry-Perot structures using low power (< 100 mW/cm2) InGaAs/GaAS quantum well lasers for a write signal.

  20. Self-organized MBE growth of II VI epilayers on patterned GaSb substrates

    NASA Astrophysics Data System (ADS)

    Wissmann, H.; Tran Anh, T.; Rogaschewski, S.; von Ortenberg, M.

    1999-05-01

    We report on the self-organized MBE growth of II-VI epilayers on patterned and unpatterned GaSb substrates resulting in quantum wires and quantum wells, respectively. The HgSe : Fe quantum wires were grown on (0 0 1)GaSb substrates with a buffer of lattice-matched ZnTe 1- xSe x. Due to the anisotropic growth of HgSe on the A-oriented stripes roof-like overgrowth with a definite ridge was obtained. Additional Fe doping in the direct vicinity of the ridge results in a highly conductive quantum wire.

  1. Enhanced magnetoresistance of Co/Cu(111) wedge superlattices grown by MBE

    NASA Astrophysics Data System (ADS)

    Xu, J.; Hickey, B. J.; Howson, M. A.; Greig, D.; Walker, M. J.; Wiser, N.

    1996-04-01

    We have grown epitaxial Co/Cu multilayer samples at different temperatures using MBE on sapphire (11 overline20)0 substrates with a 30 Å layer of Nb as a buffer, and find a remarkable correlation between the sharpness of X-ray rocking curves and the magnitude of the GMR. Whereas the peak GMR for our previous samples grown on GaAs was never greater than 26%, the maximum GMR of samples grown on sapphire under optimal growth conditions was as high as 50%.

  2. Si-doped GaAs/AlGaAs TJS laser by MBE

    SciTech Connect

    Mitsunaga, K.; Fujiwara, K.; Nunoshita, M.; Nakayama, T.

    1984-04-01

    The effect of high temperature annealing on the properties of silicon-doped GaAs/AlGaAs double heterostructure (DH) grown by molecular beam expitaxy (MBE)= and its application to the fabrication of transverse junction stripe (TJS) lasers are reported. In spite of the amphoteric nature of Si, it was found that the high temperature annealing gave little influence on the electrical and optical quality of the n-type DH wafer. The TJS laser using Si-doped GaAs/AlGaAs wafer has been oscillated cw at room temperature and exhibited low threshold current of 30 mA and high quantum efficiency of 60%.

  3. Unique cistrome defined as CsMBE is strictly required for Nrf2-sMaf heterodimer function in cytoprotection.

    PubMed

    Otsuki, Akihito; Suzuki, Mikiko; Katsuoka, Fumiki; Tsuchida, Kouhei; Suda, Hiromi; Morita, Masanobu; Shimizu, Ritsuko; Yamamoto, Masayuki

    2016-02-01

    Nrf2-small Maf (sMaf) heterodimer is essential for the inducible expression of cytoprotective genes upon exposure to oxidative and xenobiotic stresses. While the Nrf2-sMaf heterodimer recognizes DNA sequences referred to as the antioxidant/electrophile responsive element (ARE/EpRE), we here define these DNA sequences collectively as CNC-sMaf binding element (CsMBE). In contrast, large and small Maf proteins are able to form homodimers that recognize the Maf recognition element (MARE). CsMBE and MARE share a conserved core sequence but they differ in the 5'-adjacent nucleotide neighboring the core. Because of the high similarity between the CsMBE and MARE sequences, it has been unclear how many target binding sites and target genes are shared by the Nrf2-sMaf heterodimers and Maf homodimers. To address this issue, we introduced a substitution mutation of alanine to tyrosine at position 502 in Nrf2, which rendered the DNA-binding domain structure of Nrf2 similar to Maf, and generated knock-in mice expressing the Nrf2(A502Y) mutant. Our chromatin immunoprecipitation-sequencing analyses showed that binding sites of Nrf2(A502Y)-sMaf were dramatically changed from CsMBE to MARE in vivo. Intriguingly, however, one-quarter of the Nrf2(A502Y)-sMaf binding sites also bound Nrf2-sMaf commonly and vice versa. RNA-sequencing analyses revealed that Nrf2(A502Y)-sMaf failed to induce expression of major cytoprotective genes upon stress stimulation, which increased the sensitivity of Nrf2(A502Y) mutant mice to acute acetaminophen toxicity. These results demonstrate that the unique cistrome defined as CsMBE is strictly required for the Nrf2-sMaf heterodimer function in cytoprotection and that the roles played by CsMBE differ sharply from those of MARE. PMID:26677805

  4. AlGaAs/GaAs nano-hetero-epitaxy on a patterned GaAs substrate by MBE

    SciTech Connect

    Nishiwaki, T.; Yamaguchi, M.; Sawaki, N.

    2007-04-10

    An AlGaAs/GaAs resonant tunneling diode (RTD) with submicron size was fabricated on {l_brace}111{r_brace} oblique facets of GaAs with selective MBE. The method is based on the fact that a certain facet structure is formed on a patterned substrate in selective MBE because the growth rate depends strongly on the facet structure. The fabrication of a double-barrier structure was attempted on a {l_brace}111{r_brace}B facet. The current-voltage characteristics of the sample showed negative differential resistance at 77K demonstrating that we have achieved an RTD on a submicron facet.

  5. Thermal stability of MBE-grown epitaxial MoSe2 and WSe2 thin films

    NASA Astrophysics Data System (ADS)

    Chang, Young Jun; Choy, Byoung Ki; Phark, Soo-Hyon; Kim, Minu

    Layered transition metal dichalcogenides (TMDs) draw much attention, because of its unique optical properties and band structures depending on the layer thicknesses. However, MBE growth of epitaxial films demands information about thermal stability of stoichiometry and related electronic structure for high temperature range. We grow epitaxial MoSe2 and WSe2 ultrathin films by using molecular beam epitaxy (MBE). We characterize stoichiometry of films grown at various growth temperature by using various methods, XPS, EDX, and TOF-MEIS. We further test high temperature stability of electronic structure for those films by utilizing in-situ ellipsometry attached to UHV chamber. We discuss threshold temperatures up to 700~1000oC, at which electronic phases changes from semiconductor to metal due to selenium deficiency. This information can be useful for potential application of TMDs for fabrication of Van der Waals multilayers and related devices. This research was supported by Nano.Material Technology Development Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT and Future Planning. (2009-0082580), NRF-2014R1A1A1002868.

  6. MBE Growth of Ferromagnetic Metal/Compound Semiconductor Heterostructures for Spintronics

    ScienceCinema

    Palmstrom, Chris [University of California, Santa Barbara, California, United States

    2016-07-12

    Electrical transport and spin-dependent transport across ferromagnet/semiconductor contacts is crucial in the realization of spintronic devices. Interfacial reactions, the formation of non-magnetic interlayers, and conductivity mismatch have been attributed to low spin injection efficiency. MBE has been used to grow epitaxial ferromagnetic metal/GA(1-x)AL(x)As heterostructures with the aim of controlling the interfacial structural, electronic, and magnetic properties. In situ, STM, XPS, RHEED and LEED, and ex situ XRD, RBS, TEM, magnetotransport, and magnetic characterization have been used to develop ferromagnetic elemental and metallic compound/compound semiconductor tunneling contacts for spin injection. The efficiency of the spin polarized current injected from the ferromagnetic contact has been determined by measuring the electroluminescence polarization of the light emitted from/GA(1-x)AL(x)As light-emitting diodes as a function of applied magnetic field and temperature. Interfacial reactions during MBE growth and post-growth anneal, as well as the semiconductor device band structure, were found to have a dramatic influence on the measured spin injection, including sign reversal. Lateral spin-transport devices with epitaxial ferromagnetic metal source and drain tunnel barrier contacts have been fabricated with the demonstration of electrical detection and the bias dependence of spin-polarized electron injection and accumulation at the contacts. This talk emphasizes the progress and achievements in the epitaxial growth of a number of ferromagnetic compounds/III-V semiconductor heterostructures and the progress towards spintronic devices.

  7. In-situ monitoring of combinatorial laser MBE by parallel RHEED detection

    NASA Astrophysics Data System (ADS)

    Stauter, C.; Lippmaa, M.; Ohashi, S.; Kawasaki, M.; Koinuma, H.

    1998-03-01

    A combinatorial approach combined with such an atomically regulated thin film deposition technique as laser MBE can be a powerful method to search for new high Tc superconductors and quantum functional oxides. Control of the growth on an atomic scale is possible since the high vaccuum conditions involved in laser MBE allow the use of in-situ monitoring by RHEED. The necessity to control many samples deposited simultaneously during the process has induced us in implementing a RHEED beam sweeping technique: the electron beam is scanned across the substrate surface, the detection being done by a CCD camera looking at the RHEED screen. Using this technique, we have made it possible to control simultaneously the growth of several oxide films at a practical rate. Furthermore, variations of growth rate across the substrate surface caused by plume or temperature gradients have been observed. Interesting applications that can be derived include the possibilty to test quickly many different growth conditions before optimization and the one-by-one evaluation of the influence of deposition parameters.

  8. 40 CFR 33.407 - How long do MBE and WBE fair share objectives remain in effect?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 1 2011-07-01 2011-07-01 false How long do MBE and WBE fair share objectives remain in effect? 33.407 Section 33.407 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... objectives. The fact that a disparity study utilized in negotiating fair share objectives has become...

  9. MBE HgCdTe for HDVIP Devices: Horizontal Integration in the US HgCdTe FPA Industry

    NASA Astrophysics Data System (ADS)

    Aqariden, F.; Elsworth, J.; Zhao, J.; Grein, C. H.; Sivananthan, S.

    2012-10-01

    Molecular beam epitaxy (MBE) growth of HgCdTe offers the possibility of fabricating multilayer device structures with an almost unlimited choice of infrared sensor designs for focal-plane array (FPA) fabrication. HgCdTe offers two major advantages that explain its dominance in the infrared photon detector marketplace. The thermal generation rate per unit volume of the material is lower and the quantum efficiency for photon absorption in the infrared is higher in HgCdTe than in any competing material—it yields devices with quantum efficiencies as high as 0.99. Recently, EPIR Technologies and DRS Infrared Technologies agreed to collaborate and examine: (i) the feasibility of employing MBE HgCdTe in the fabrication of high-density vertically interconnected photodiodes (HDVIPs), which are usually fabricated with liquid-phase epitaxy material, and (ii) the potential benefits of horizontal integration, with EPIR supplying the MBE materials to DRS for device and array fabrication. The team designed and developed passivation-absorber-passivation structures that are heavily used by DRS. This paper provides an overview of the characteristics of HDVIP devices and arrays fabricated from MBE HgCdTe and the anticipated advantages of horizontal integration in the industry. Material growth, device fabrication, and test results are presented.

  10. Nitride-MBE system for in situ synchrotron X-ray measurements

    NASA Astrophysics Data System (ADS)

    Sasaki, Takuo; Ishikawa, Fumitaro; Yamaguchi, Tomohiro; Takahasi, Masamitu

    2016-05-01

    A molecular beam epitaxy (MBE) chamber dedicated to nitride growth was developed at the synchrotron radiation facility SPring-8. This chamber has two beryllium windows for incident and outgoing X-rays, and is directly connected to an X-ray diffractometer, enabling in situ synchrotron X-ray measurements during the nitride growth. Experimental results on initial growth dynamics in GaN/SiC, AlN/SiC, and InN/GaN heteroepitaxy were presented. We achieved high-speed and high-sensitivity reciprocal space mapping with a thickness resolution of atomic-layer scale. This in situ measurement using the high-brilliance synchrotron light source will be useful for evaluating structural variations in the initial growth stage of nitride semiconductors.

  11. Synthesis and characterizations of nanoscale single crystal GaN grown by ion assisted gas source MBE

    NASA Astrophysics Data System (ADS)

    Cui, Bentao; Cohen, P. I.

    2004-03-01

    Nanoscale patterns could be induced by ion bombardment [1, 2]. In this study, an in-situ real time light scattering technique, combined with Reflection High Energy Electron Diffraction (RHEED), were used to study the surface morphology evolution during the ion beam assisted growth of GaN in a gas source MBE system. Ga was provided by a thermal effusion cell. Ammonia was used as the nitrogen source. A hot-filament Kaufman ion source was used to supply sub-KeV ion beams. Sapphire and MOCVD GaN templates were used as the substrates. A custom-designed Desorption Mass Spectrometer (DMS) was used to calibrate the growth temperature and determine the growth rate. Before growing GaN, the sapphire substrates were pretreated in an ion flux and then annealed for cleaning. The sapphire surface was then nitrided in ammonia at 1100K for about 10 min. After nitridation, a thin GaN buffer layer was prepared by a sequence of adsorption and annealing steps. During the growth, the short-range surface morphology and film quality were monitored in situ by RHEED. In a real-time way, the long-range surface morphology was monitored in-situ by light scattering technique. Photodiode array detector and CCD camera were used to record the reflected light scattering intensity and spectra profile respectively. Periodical patterns, such as ripple, have been observed during ion bombardment on GaN with or without growth. A linear theory (from Bradley and Harper 1988 [3]) has been modified to explain the dependence of ripple wavelength on ion species and ion energy. Partially supported by the National Science Foundation and the Air Force Office of Scientific Research. [1]. J. Erlebacher, M. J. Aziz, E. Chason, M. B. Sinclair, and J. A. Floro, Phys. Rev. Lett. 82, 2330 (1998); J. Erlebacher, M. J. Aziz, E. Chason, M. B. Sinclair, and J. A. Floro, Phys. Rev. Lett. 84, 5800 (2000). [2]. S. Facsko, T. Dekorsy, C. Koerdt, C. Trappe, H. Kurz, A. Vogt et al.. Science 285, 1551 (1999). [3]. R. M. Bradley

  12. Specific features of NH{sub 3} and plasma-assisted MBE in the fabrication of III-N HEMT heterostructures

    SciTech Connect

    Alexeev, A. N.; Krasovitsky, D. M.; Petrov, S. I.; Chaly, V. P.; Mamaev, V. V.; Sidorov, V. G.

    2015-01-15

    The specific features of how nitride HEMT heterostructures are produced by NH{sub 3} and plasma-assisted (PA) molecular-beam epitaxy (MBE) are considered. It is shown that the use of high-temperature AlN/AlGaN buffer layers grown with ammonia at extremely high temperatures (up to 1150°C) can drastically improve the structural perfection of the active GaN layers and reduce the dislocation density in these layers to values of 9 × 10{sup 8}−1 × 10{sup 9} cm{sup −2}. The use of buffer layers of this kind makes it possible to obtain high-quality GaN/AlGaN heterostructures by both methods. At the same time, in contrast to ammonia MBE which is difficult to apply at T < 500°C (because of the low efficiency of ammonia decomposition), PA MBE is rather effective at low temperatures, e.g., for the growth of InAlN layers lattice-matched with GaN. The results obtained in the MBE growth of AlN/AlGaN/GaN/InAlN heterostructures by both PA-MBE and NH{sub 3}-MBE with an extremely high ammonia flux are demonstrated.

  13. Structural characterization of Nb on sapphire as a buffer layer for MBE growth

    NASA Astrophysics Data System (ADS)

    Reimer, P. M.; Zabel, H.; Flynn, C. P.; Dura, J. A.

    1993-02-01

    Niobium films grown by molecular beam epitaxy on sapphire substrates are among the highest quality ones that thin-film metal science has yet produced. This system is in intense use as a buffer layer for epitaxial growth of other metal thin films, magnetic films and superlattices as well. We studied films of Nb [110] deposited by MBE on Al 2O 3 [11 overline20] substrates using high-precision X-ray diffraction. Rocking curves of the out-of-plane Nb (110) peak reveal a two-component line shape. The sharper component implies a mosaic distribution an order of magnitude sharper than bulk single crystal Nb and a transverse structural coherence length exceeding 10 3 nm. The atomic planes associated with the sharp component are exactly aligned with the sapphire (11 overline20) planes, while those associated with the broad component are slightly misaligned. Upon loading the Nb film with a small amount of hydrogen, we find a further, dramatic increase of the lateral coherence length. The resulting mosaic distribution of the sharp component appears to be limited only by that of the sapphire substrate. We will discuss the results in terms of strain relief by hydrogen-induced dislocation motion.

  14. MBE fabrication of self-assembled Si and metal nanostructures on Si surfaces

    SciTech Connect

    Galiana, Natalia; Martin, Pedro-Pablo; Munuera, Carmen; Varela del Arco, Maria; Soria, Federico; Ocal, Carmen; Ruiz, Ana; Alonso, Maria

    2006-01-01

    Two types of fairly regular distributions of Si nanostructures, of interest as templates to grow spatially controlled ensembles of metal (Co, Fe, Ag, etc.) nanostructures, are presented in this paper. Both of them are achieved by self-assembling processes during Si homoepitaxy. One corresponds to films grown by molecular beam epitaxy (MBE) on Si(0 0 1)-2 x 1 surfaces with low (<1 degree) miscut angles. In this case, arrays of 3D Si-islands displaying well defined pyramid-like shapes can be obtained, as evidenced by Scanning Force Microscopy (SFM) and Scanning Transmission Electron Microscopy (STEM). Such arrays exhibit strong similarities with those reported for Ge and SiGe islands on Si(0 0 1), and may thus serve as a simpler route to produce ordered distributions of metallic nanodots. On the other hand, on Si(1 1 1)-7 x 7 vicinal substrates misoriented 4 degrees toward the View the MathML source direction, step rearrangement during homoepitaxy permits to produce nanopatterned surfaces, the building-blocks of which are triangular (1 1 1) platforms, with lateral dimensions of hundreds of nanometers, bound by step bunches about 30 nm high. Furthermore, different Ag deposition experiments support this spontaneous patterning on Si(1 1 1) as a promising approach to achieve regular distributions of metallic nanocrystals with an overall homogeneity in sizes, shapes and spacing.

  15. Capture kinetics at deep-level defects in MBE-grown CdTe layers

    NASA Astrophysics Data System (ADS)

    Olender, Karolina; Wosinski, Tadeusz; Makosa, Andrzej; Kret, Slawomir; Kolkovsky, Valery; Karczewski, Grzegorz

    2011-04-01

    The results of deep-level transient spectroscopy (DLTS) investigations in n-type CdTe layers grown by the molecular-beam epitaxy (MBE) technique on lattice-mismatched GaAs substrates are described. Three electron traps and one hole trap, at rather low concentrations of the order of 1013 cm-3, have been revealed in the DLTS spectra measured under various bias conditions of Schottky diodes prepared on the as-grown CdTe layers. One of the electron traps has been attributed to electron states of dislocations on the ground of the logarithmic capture kinetics for capture of electrons into the trap states. The other three traps, displaying exponential capture kinetics, have been attributed to native point defects produced during the epitaxial growth of CdTe. The microscopic nature of the defects responsible for the traps is discussed taking into account recent results of first-principles calculations of the properties of dominant native defects in CdTe.

  16. MBE growth of active regions for electrically pumped, cw-operating GaSb-based VCSELs

    NASA Astrophysics Data System (ADS)

    Kashani-Shirazi, K.; Bachmann, A.; Boehm, G.; Ziegler, S.; Amann, M.-C.

    2009-03-01

    Electrically pumped, cw-operating, single-mode GaSb-based VCSELs are attractive light sources for trace-gas sensing systems using tunable diode laser absorption spectroscopy (TDLAS) [A. Vicet, D.A. Yarekha, A. Pérona, Y. Rouillard, S. Gaillard, Spectrochimica Acta Part A 58 (2002) 2405-2412]. Only recently, the first electrically pumped (EP) devices emitting at 2.325 μm in cw-mode at room temperature have been reported [A. Bachmann, T. Lim, K. Kashani-Shirazi, O. Dier, C. Lauer, M.-C. Amann, Electronics Letters 44(3) (2008) 202-203]. The fabrication of these devices employs the molecular beam epitaxy (MBE) growth of GaSb/AlAsSb-distributed Bragg mirrors, a multi-quantum-well active region made of AlGaAsSb/InGaAsSb and an InAsSb/GaSb-buried-tunnel junction. As VCSELs are usually driven under high injection rates, an optimum electrical design of active regions is essential for high-performance devices. In this paper we present an enhanced simulation of current flow in the active region under operation conditions. The calculation includes carrier transport by drift, diffusion and tunneling. We discuss different design criteria and material compositions for active regions. Active regions with various barrier materials were incorporated into edge emitter samples to evaluate their performance. Aluminum-containing barriers show better internal efficiency compared to active regions with GaSb as the barrier material.

  17. On the Phase Shift of RHEED Intensity Oscillation during Homoepitaxy by MBE

    NASA Astrophysics Data System (ADS)

    Shin, B.; Leonard, J. P.; McCamy, J. W.; Aziz, M. J.

    2006-03-01

    Despite the widespread usage of RHEED over many years, there still remain fundamental questions unanswered with regard to the interpretation of RHEED measurements. One of these issues is the phase shift of the RHEED intensity oscillations upon changing the incidence angle of electron beams. Therefore, we have conducted a systematic investigation of the phase shift of the RHEED intensity oscillations during homoepitaxy of Ge(001) by MBE for a wide range of diffraction conditions. Our results show that for small incidence angles with a beam azimuth several degrees away from crystallographic symmetry directions, the phase stays the same; it starts to shift once the (004) Kikuchi line appears in the RHEED pattern. Moreover, under some conditions we observe the oscillations from only the Kikuchi feature and not from the specular spot, and the oscillatory behavior of the Kikuchi feature is almost out of phase with that of the specular spot. All these results convincingly demonstrate that the phase shift is caused by the interference of the specular spot by the Kikuchi features. The lesson that can be learned from our study is that in order to use the RHEED specular intensity oscillation to learn about surface morphology, one must be extremely careful that the RHEED measurements be conducted under conditions where the influence of the Kikuchi features is minimal.

  18. Group III-nitride thin films grown using MBE and bismuth

    DOEpatents

    Kisielowski, Christian K.; Rubin, Michael

    2000-01-01

    The present invention comprises growing gallium nitride films in the presence of bismuth using MBE at temperatures of about 1000 K or less. The present invention further comprises the gallium nitride films fabricated using the inventive fabrication method. The inventive films may be doped with magnesium or other dopants. The gallium nitride films were grown on sapphire substrates using a hollow anode Constricted Glow Discharge nitrogen plasma source. When bismuth was used as a surfactant, two-dimensional gallium nitride crystal sizes ranging between 10 .mu.m and 20 .mu.m were observed. This is 20 to 40 times larger than crystal sizes observed when GaN films were grown under similar circumstances but without bismuth. It is thought that the observed increase in crystal size is due bismuth inducing an increased surface diffusion coefficient for gallium. The calculated value of 4.7.times.10.sup.-7 cm.sup.2 /sec. reveals a virtual substrate temperature of 1258 K which is 260 degrees higher than the actual one.

  19. Group III-nitride thin films grown using MBE and bismuth

    DOEpatents

    Kisielowski, Christian K.; Rubin, Michael

    2002-01-01

    The present invention comprises growing gallium nitride films in the presence of bismuth using MBE at temperatures of about 1000 K or less. The present invention further comprises the gallium nitride films fabricated using the inventive fabrication method. The inventive films may be doped with magnesium or other dopants. The gallium nitride films were grown on sapphire substrates using a hollow anode Constricted Glow Discharge nitrogen plasma source. When bismuth was used as a surfactant, two-dimensional gallium nitride crystal sizes ranging between 10 .mu.m and 20 .mu.m were observed. This is 20 to 40 times larger than crystal sizes observed when GaN films were grown under similar circumstances but without bismuth. It is thought that the observed increase in crystal size is due bismuth inducing an increased surface diffusion coefficient for gallium. The calculated value of 4.7.times.10.sup.-7 cm.sup.2 /sec. reveals a virtual substrate temperature of 1258 K which is 260 degrees higher than the actual one.

  20. MBE growth and characterization of TlInGaAsN double quantum well structures

    NASA Astrophysics Data System (ADS)

    Krishnamurthy, D.; Shanthi, S.; Kim, K. M.; Sakai, Y.; Ishimaru, M.; Hasegawa, S.; Asahi, H.

    2009-03-01

    In the pursuit of reducing the temperature dependence of the emission wavelengths of devices, TlInGaAsN double quantum well (DQW) structures with different barriers grown on GaAs substrates by molecular beam epitaxy (MBE) were investigated. Higher Tl incorporation, a key parameter to reduce temperature dependence, could be obtained in the TlGaAsN barrier samples. However, the presence of many dislocations and very rough interfaces together with phase separation reduced the photoluminescence (PL) characteristics. DQW structures with combined barriers of TlGaAsN+TlGaAs+TlGaAsN and those consisting of TlGaAsN with reduced N composition showed improved crystalline characteristics. The (2 2 4) reciprocal space maps of these two samples did not show any diffraction corresponding to phase segregation. However, cross-sectional transmission electron microscopy (X-TEM) images revealed the presence of inhomogeneity (i.e., the presence of nearly perfect regions with good interfaces as well as regions with rough interfaces) in these samples.

  1. Characterization of ZnSe homo-interface grown by MBE

    NASA Astrophysics Data System (ADS)

    Nakanishi, F.; Doi, H.; Yamada, T.; Matsuoka, T.; Nishine, S.; Matsumoto, K.; Shirakawa, T.

    1997-06-01

    A ZnSe homo-interface, which was formed by MBE, was characterized. First, when the unetched ZnSe substrates were used, 3D-nucleation occurred, which suggested the remnant of the heterogeneous nuclei. Consequently, the interface layer was clearly visible and as high as 10 8 cm -2 crystal defects, such as dislocations and stacking faults, were observed by cross sectional TEM. The EPD was uncountable at this high defect density. Second, when the substrates were chemically etched, 2D-nucleation was confirmed by RHEED, and interface layer and defects were not observed by cross sectional TEM. However plan-view TEM and EPD revealed that about 10 6-10 7 cm -2 crystal defects were observed. To clarify the origin of the crystal defects at the homo-interface, SIMS analysis was performed and the results showed the pile up of oxygen at the interface, and the EPD was proportional to the intensity of the O signal. Finally, the reduction of the oxide layer after the chemical etching was tried using various reagents. The reconstruction pattern of the RHEED was observed at lower temperatures using HCl solution and the EPD was lowered near the level of the ZnSe substrates, 10 4-10 5 cm -2

  2. Impact of LT-GaAs layers on crystalline properties of the epitaxial GaAs films grown by MBE on Si substrates

    NASA Astrophysics Data System (ADS)

    Petrushkov, M. O.; Putyato, M. A.; Gutakovsky, A. K.; Preobrazhenskii, V. V.; Loshkarev, I. D.; Emelyanov, E. A.; Semyagin, B. R.; Vasev, A. V.

    2016-08-01

    GaAs films with low-temperature GaAs (LT-GaAs) layers were grown by molecular beam epitaxy (MBE) method on vicinal (001) Si substrates oriented 6° off towards [110]. The grown structures were different with the thickness of LT-GaAs layers and its arrangement in the film. The processes of epitaxial layers nucleation and growth were controlled by reflection high energy electron diffraction (RHEED) method. Investigations of crystalline properties of the grown structures were carried out by the methods of X-ray diffraction (XRD) and transmission electron microscopy (TEM). The crystalline perfection of the GaAs films with LT-GaAs layers and the GaAs films without ones was comparable. It was found that in the LT- GaAs/Si layers the arsenic clusters are formed, as it occurs in the LT-GaAs/GaAs system without dislocation. It is shown that large clusters are formed mainly on the dislocations. However, the clusters have practically no effect on the density and the propagation path of threading dislocations. With increasing thickness of LT-GaAs layer the dislocations are partly bent along the LT-GaAs/GaAs interface due to the presence of stresses.

  3. Magnetism and Nanoscale Structural and Compositional Irregularities in MBE-grown La2MnNiO6 on SrTiO3(001)

    NASA Astrophysics Data System (ADS)

    Chambers, Scott; Du, Yingge; Droubay, Timothy; Sushko, Peter; Spurgeon, Steven; Devaraj, Arun; Bowden, Mark; Shutthanandan, V.; Gustafsson, Torgny

    Double perovskites (A2BB'O6) are a fascinating class of oxides with considerable potential for applications requiring ferromagnetic and semiconducting properties. We have investigated MBE-grown La2MnNiO6 and have found that despite the fact that Mn and Ni are present as 4 + (d 3 : t2g 3eg0) and 2 + (d 8 : t2g 6eg2) respectively, and exhibit suitable XMCD signatures, the volume-averaged moment per formula unit is considerably less than 5 Bohr magnetons. Our electron energy loss spectroscopy (STEM-EELS) and atom probe tomography (APT) results to date reveal that there is considerable disorder in the B-site sublattice for as-deposited films, despite excellent volume-averaged stoichiometry. While air annealing results in substantial ordering, the moment remains low due to the nucleation of NiO inclusions with needle-like shapes revealed only by APT. First principles modeling suggests that even though the double perovskite is quite stable if nucleated in excess O, the presence of O vacancies facilitates structural disorder. In this talk, we will present our latest results on this fascinating material.

  4. Controlling the compositional inhomogeneities in AlxGa1-xN/AlyGa1-yN MQWs grown by PA-MBE: Effect on luminescence properties

    NASA Astrophysics Data System (ADS)

    Pramanik, Pallabi; Sen, Sayantani; Singha, Chirantan; Roy, Abhra Shankar; Das, Alakananda; Sen, Susanta; Bhattacharyya, Anirban; Kumar, Deepak; Sridhara Rao, D. V.

    2016-04-01

    Al0.35Ga0.65N/Al0.55Ga0.45N MQWs were grown by PA-MBE using a range of group III/V flux ratios. TEM images indicate sharp interfaces and well/barrier widths of 1.5/2 nm. We observe that small variations of group III/V flux ratio cause dramatic variations in the room temperature photoluminescence (PL) spectra. In addition to band edge luminescence, multiple low energy PL peaks are observed for growths under excess group III conditions, which are absent for near-stoichiometric growth. Temperature dependent PL measurements indicate that at room temperature, emission occurs due to transitions at potential fluctuations generated by the presence of compositional inhomogeneity. These effects are dominant for growth under excess group III conditions due to the presence of a metallic layer on the growth surface during deposition. This can be eliminated by the use of an Indium surfactant during growth, which modifies the diffusion length of Ga and Al adatoms. Under these conditions, the optical properties of MQWs are relatively insensitive to variations in group III to V flux ratio and hence substrate temperature, thus making them suitable for industrial-scale fabrication of optoelectronic devices in the ultraviolet range.

  5. Self-regulating MBE growth of stoichiometric BaSnO3 films via reactive radical mechanism

    NASA Astrophysics Data System (ADS)

    Prakash, Abhinav; Dewey, John; Yun, Hwanhui; Jeong, Jong Seok; Mkhoyan, K. Andre; Jalan, Bharat

    Growth of thin films comprising of element with low oxidation potential such as Sn often requires reactive oxidants such as ozone or high-pressure oxygen plasma. By utilizing the chemistry of highly reactive radical of Sn, we will present on the growth of phase-pure, epitaxial BaSnO3 films using a hybrid molecular beam epitaxy (MBE) approach with scalable growth rates. The notable finding was that Sn radicals are very reactive to yield phase-pure BaSnO3 films even in molecular oxygen. In this approach, we use hexamethylditin (HMDT) as a tin source, a solid effusion cell for Ba and either molecular oxygen or an rf oxygen plasma source. Phase-pure BaSnO3 films were grown at 900 0C, and oxygen pressure of 5x10-6 Torr as a function Sn:Ba ratio. In-situ time-dependent RHEED intensity oscillations were observed establishing a layer-by-layer growth mode and a critical thickness of ~1 nm for strain relaxation. Rutherford backscattering spectrometry and lattice constant determined using high-resolution X-ray diffraction was used to optimize cation stoichiometry. ``MBE growth window'' was identified where films show bulk-like lattice parameter (4.116 Å) over a wide-range of cation flux ratios. A correlation between RHEED patterns, stoichiometry, and surface morphology was established This work is supported primarily by NSF (DMR-1410888).

  6. GaAsPN-based PIN solar cells MBE-grown on GaP substrates: toward the III-V/Si tandem solar cell

    NASA Astrophysics Data System (ADS)

    Da Silva, M.; Almosni, S.; Cornet, C.; Létoublon, A.; Levallois, C.; Rale, P.; Lombez, L.; Guillemoles, J.-F.; Durand, O.

    2015-03-01

    GaAsPN semiconductors are promising material for the elaboration of high efficiencies tandem solar cells on silicon substrates. GaAsPN diluted nitride alloy is studied as the top junction material due to its perfect lattice matching with the Si substrate and its ideal bandgap energy allowing a perfect current matching with the Si bottom cell. We review our recent progress in materials development of the GaAsPN alloy and our recent studies of some of the different building blocks toward the elaboration of a PIN solar cell. A lattice matched (with a GaP(001) substrate, as a first step toward the elaboration on a Si substrate) 1μm-thick GaAsPN alloy has been grown by MBE. After a post-growth annealing step, this alloy displays a strong absorption around 1.8-1.9 eV, and efficient photoluminescence at room temperature suitable for the elaboration of the targeted solar cell top junction. Early stage GaAsPN PIN solar cells prototypes have been grown on GaP (001) substrates, with 2 different absorber thicknesses (1μm and 0.3μm). The external quantum efficiencies and the I-V curves show that carriers have been extracted from the GaAsPN alloy absorbers, with an open-circuit voltage of 1.18 V, while displaying low short circuit currents meaning that the GaAsPN structural properties needs a further optimization. A better carrier extraction has been observed with the absorber displaying the smallest thickness, which is coherent with a low carriers diffusion length in our GaAsPN compound. Considering all the pathways for improvement, the efficiency obtained under AM1.5G is however promising.

  7. Nanoscale Probing of Local Electrical Characteristics on MBE-Grown Bi₂Te₃ Surfaces under Ambient Conditions.

    PubMed

    Macedo, Rita J; Harrison, Sara E; Dorofeeva, Tatiana S; Harris, James S; Kiehl, Richard A

    2015-07-01

    The local electrical characteristics on the surface of MBE-grown Bi2Te3 are probed under ambient conditions by conductive atomic force microscopy. Nanoscale mapping reveals a 10-100× enhancement in current at step-edges compared to that on terraces. Analysis of the local current-voltage characteristics indicates that the transport mechanism is similar for step-edges and terraces. Comparison of the results with those for control samples shows that the current enhancement is not a measurement artifact but instead is due to local differences in electronic properties. The likelihood of various possible mechanisms is discussed. The absence of enhancement at the step-edges for graphite terraces is consistent with the intriguing possibility that spin-orbit coupling and topological effects play a significant role in the step-edge current enhancement in Bi2Te3.

  8. Possibilities for LWIR detectors using MBE-grown Si(/Si(1-x)Ge(x) structures

    NASA Technical Reports Server (NTRS)

    Hauenstein, Robert J.; Miles, Richard H.; Young, Mary H.

    1990-01-01

    Traditionally, long wavelength infrared (LWIR) detection in Si-based structures has involved either extrinsic Si or Si/metal Schottky barrier devices. Molecular beam epitaxially (MBE) grown Si and Si/Si(1-x)Ge(x) heterostructures offer new possibilities for LWIR detection, including sensors based on intersubband transitions as well as improved conventional devices. The improvement in doping profile control of MBE in comparison with conventional chemical vapor deposited (CVD) Si films has resulted in the successful growth of extrinsic Si:Ga, blocked impurity-band conduction detectors. These structures exhibit a highly abrupt step change in dopant profile between detecting and blocking layers which is extremely difficult or impossible to achieve through conventional epitaxial growth techniques. Through alloying Si with Ge, Schottky barrier infrared detectors are possible, with barrier height values between those involving pure Si or Ge semiconducting materials alone. For both n-type and p-type structures, strain effects can split the band edges, thereby splitting the Schottky threshold and altering the spectral response. Measurements of photoresponse of n-type Au/Si(1-x)Ge(x) Schottky barriers demonstrate this effect. For intersubband multiquntum well (MQW) LWIR detection, Si(1-x)Ge(x)/Si detectors grown on Si substrates promise comparable absorption coefficients to that of the Ga(Al)As system while in addition offering the fundamental advantage of response to normally incident light as well as the practical advantage of Si-compatibility. Researchers grew Si(1-x)Ge(x)/Si MQW structures aimed at sensitivity to IR in the 8 to 12 micron region and longer, guided by recent theoretical work. Preliminary measurements of n- and p-type Si(1-x)Ge(x)/Si MQW structures are given.

  9. Novel InGaAs contact layer growth for hetero-junction bipolar transistors (HBTs) by using the multiple group-V source molecular beam epitaxy (MBE) system

    NASA Astrophysics Data System (ADS)

    Kadoiwa, Kaoru; Izumi, Shigekazu; Yamamoto, Yoshitsugu; Hayafuji, Norio; Sonoda, Takuji

    1999-05-01

    Dependence of layer surface morphology and electrical properties on growth conditions, growth temperature and supplying conditions of group-V sources such as solid-As and AsH 3 hydride gas, has been investigated with specially designed MBE system, including both solid-As source cell and gas source cracking cell, for highly lattice-mismatched (+4%) In 0.5Ga 0.5As layer grown on GaAs. We demonstrate that utilizing of AsH 3 hydride source enables us to obtain a superior smooth surface in comparison with utilizing solid-As source. The HAZE level for the former source is reduced to one twentieth of the latter. The advantage of gas-source MBE (GS-MBE) method (hydrogen effect) was realized as suppressing In segregation. The effective hydrogen comes from AsH 3 hydride that acts as the surfactant that controls coherent small 3D islands formation during initial growth stage. The optimized GS-MBE growth method, under AsH 3 flow rate of 3 SCCM and growth temperature of 470°C, establishes that the In xGa 1- xAs ( x=0.6) layer grown on GaAs with the surface is as smooth as the surface of GaAs substrate, and also shows the contact resistance to be 4×10 -8 Ω cm 2. This value is well-fitted for nonalloy ohmic contact by using W/Si as emitter electrodes for HBTs.

  10. High Quality GaAs Growth by MBE on Si Using GeSi Buffers and Prospects for Space Photovoltaics

    NASA Technical Reports Server (NTRS)

    Carlin, J. A.; Ringel, S. A.; Fitzgerald, E. A.; Bulsara, M.

    2005-01-01

    III-V solar cells on Si substrates are of interest for space photovoltaics since this would combine high performance space cells with a strong, lightweight and inexpensive substrate. However, the primary obstacles blocking III-V/Si cells from achieving high performance to date have been fundamental materials incompatabilities, namely the 4% lattice mismatch between GaAs and Si, and the large mismatch in thermal expansion coefficient. In this paper, we report on the molecular beam epitaxial (MBE) growth and properties of GaAs layers and single junction GaAs cells on Si wafers which utilize compositionally graded GeSi Intermediate buffers grown by ultra-high vacuum chemical vapor deposition (UHVCVD) to mitigate the large lattice mismatch between GaAs and Si. Ga As cell structures were found to incorporate a threading dislocation density of 0.9-1.5 x 10 (exp 6) per square centimeter, identical to the underlying relaxed Ge cap of the graded buffer, via a combination of transmission electron microscopy, electron beam induced current, and etch pit density measurements. AlGaAs/GaAs double heterostructures wre grown on the GeSi/Si substrates for time-resolved photoluminescence measurements, which revealed a bulk GaAs minority carrier lifetime in excess of 10 ns, the highest lifetime ever reported for GaAs on Si. A series of growth were performed to ass3ss the impact of a GaAs buffer to a thickness of only 0.1 micrometer. Secondary ion mass spectroscopy studies revealed that there is negligible cross diffusion of Ga, As and Ge at he III-V/Ge interface, identical to our earlier findings for GaAs grown on Ge wafers using MBE. This indicates that there is no need for a buffer to "bury" regions of high autodopjing,a nd that either pn or np configuration cells are easily accomodated by these substrates. Preliminary diodes and single junction Al Ga As heteroface cells were grown and fabricated on the Ge/GeSi/Si substrates for the first time. Diodes fabricated on GaAs, Ge and Ge

  11. A new approach to epitaxially grow high-quality GaN films on Si substrates: the combination of MBE and PLD

    PubMed Central

    Wang, Wenliang; Wang, Haiyan; Yang, Weijia; Zhu, Yunnong; Li, Guoqiang

    2016-01-01

    High-quality GaN epitaxial films have been grown on Si substrates with Al buffer layer by the combination of molecular beam epitaxy (MBE) and pulsed laser deposition (PLD) technologies. MBE is used to grow Al buffer layer at first, and then PLD is deployed to grow GaN epitaxial films on the Al buffer layer. The surface morphology, crystalline quality, and interfacial property of as-grown GaN epitaxial films on Si substrates are studied systematically. The as-grown ~300 nm-thick GaN epitaxial films grown at 850 °C with ~30 nm-thick Al buffer layer on Si substrates show high crystalline quality with the full-width at half-maximum (FWHM) for GaN(0002) and GaN(102) X-ray rocking curves of 0.45° and 0.61°, respectively; very flat GaN surface with the root-mean-square surface roughness of 2.5 nm; as well as the sharp and abrupt GaN/AlGaN/Al/Si hetero-interfaces. Furthermore, the corresponding growth mechanism of GaN epitaxial films grown on Si substrates with Al buffer layer by the combination of MBE and PLD is hence studied in depth. This work provides a novel and simple approach for the epitaxial growth of high-quality GaN epitaxial films on Si substrates. PMID:27101930

  12. A new approach to epitaxially grow high-quality GaN films on Si substrates: the combination of MBE and PLD.

    PubMed

    Wang, Wenliang; Wang, Haiyan; Yang, Weijia; Zhu, Yunnong; Li, Guoqiang

    2016-04-22

    High-quality GaN epitaxial films have been grown on Si substrates with Al buffer layer by the combination of molecular beam epitaxy (MBE) and pulsed laser deposition (PLD) technologies. MBE is used to grow Al buffer layer at first, and then PLD is deployed to grow GaN epitaxial films on the Al buffer layer. The surface morphology, crystalline quality, and interfacial property of as-grown GaN epitaxial films on Si substrates are studied systematically. The as-grown ~300 nm-thick GaN epitaxial films grown at 850 °C with ~30 nm-thick Al buffer layer on Si substrates show high crystalline quality with the full-width at half-maximum (FWHM) for GaN(0002) and GaN(102) X-ray rocking curves of 0.45° and 0.61°, respectively; very flat GaN surface with the root-mean-square surface roughness of 2.5 nm; as well as the sharp and abrupt GaN/AlGaN/Al/Si hetero-interfaces. Furthermore, the corresponding growth mechanism of GaN epitaxial films grown on Si substrates with Al buffer layer by the combination of MBE and PLD is hence studied in depth. This work provides a novel and simple approach for the epitaxial growth of high-quality GaN epitaxial films on Si substrates.

  13. A study of the preparation of epitaxy-ready polished surfaces of (100) Gallium Antimonide substrates demonstrating ultra-low surface defects for MBE growth

    NASA Astrophysics Data System (ADS)

    Martinez, Rebecca; Tybjerg, Marius; Flint, Patrick; Fastenau, Joel; Lubyshev, Dmitri; Liu, Amy W. K.; Furlong, Mark J.

    2016-05-01

    Gallium Antimonide (GaSb) is an important Group III-V compound semiconductor which is suitable for use in the manufacture of a wide variety of optoelectronic devices such as infra-red (IR) focal plane detectors. A significant issue for the commercialisation of these products is the production of epitaxy ready GaSb, which remains a challenge for the substrate manufacturer, as the stringent demands of the MBE process, requires a high quality starting wafer. In this work large diameter GaSb crystals were grown by the Czochralski (Cz) method and wafers prepared for chemo-mechanical polishing (CMP). Innovative epi-ready treatments and novel post polish cleaning methodologies were applied. The effect of these modified finishing chemistries on substrate surface quality and the performance of epitaxially grown MBE GaSb IR detector structures were investigated. Improvements in the lowering of surface defectivity, maintaining of the surface roughness and optimisation of all flatness parameters is confirmed both pre and post MBE growth. In this paper we also discuss the influence of bulk GaSb quality on substrate surface performance through the characterisation of epitaxial structures grown on near zero etch pit density (EPD) crystals. In summary progression and development of current substrate polishing techniques has been demonstrated to deliver a consistent improved surface on GaSb wafers with a readily desorbed oxide for epitaxial growth.

  14. Formation of self-organized quantum dot structures and quasi-perfect CuPt-type ordering by gas-source MBE growth of (GaP){sub n}(InP){sub n} superlattices

    SciTech Connect

    Kim, S.J.; Asahi, H.; Takemoto, M.; Asami, K.; Takeuchi, M.; Gonda, S.

    1996-12-31

    (GaP){sub n}(InP){sub n} short period superlattices (SLs) are grown on GaAs(N11) substrates by gas-source MBE. Transmission electron microscopy observations show that the SLs grown on GaAs(311)A and (411)A have dot structures with a size of about 10--20nm. Photoluminescence (PL) peak energies are greatly dependent on substrate orientation and monolayer number n. On the other hand, the (GaP){sub 1}(InP){sub 1} SLs grown on (111) have no composition modulation and have quasi-perfect CuPt-type ordering along the [111] growth direction. The PL peak energy is 321 meV lower than that of disordered InGaP alloy. Self-organized (GaP){sub n}(InP){sub m} SL(dot/barrier)/In{sub 0.49}Ga{sub 0.51}P(barrier) quantum dot structures exhibit strong 77K PL with a full width at half maximum of about 70 meV.

  15. Vanadium dioxide thin films prepared on silicon by low temperature MBE growth and ex-situ annealing

    NASA Astrophysics Data System (ADS)

    Homm, Pia; van Bilzen, Bart; Menghini, Mariela; Locquet, Jean-Pierre; Ivanova, Todora; Sanchez, Luis; Sanchis, Pablo

    Vanadium dioxide (VO2) is a material that shows an insulator to metal transition (IMT) near room temperature. This property can be exploited for applications in field effect devices, electro-optical switches and nonlinear circuit components. We have prepared VO2 thin films on silicon wafers by combining a low temperature MBE growth with an ex-situ annealing at high temperature. We investigated the structural, electrical and optical characteristics of films with thicknesses ranging from 10 to 100 nm. We have also studied the influence of the substrate cleaning. The films grown with our method are polycrystalline with a preferred orientation in the (011) direction of the monoclinic phase. For the films produced on silicon with a native oxide, an IMT at around 75 °C is observed. The magnitude of the resistance change across the IMT decreases with thickness while the refractive index at room temperature corresponds with values reported in the literature for thin films. The successful growth of VO2 films on silicon with good electrical and optical properties is an important step towards the integration of VO2 in novel devices. The authors acknowledge financial support from the FWO project G052010N10 and EU-FP7 SITOGA project. PH acknowledges support from Becas Chile - CONICYT.

  16. Dynamic Curvature and Stress Studies for MBE CdTe on Si and GaAs Substrates

    NASA Astrophysics Data System (ADS)

    Jacobs, R. N.; Jaime Vasquez, M.; Lennon, C. M.; Nozaki, C.; Almeida, L. A.; Pellegrino, J.; Arias, J.; Taylor, C.; Wissman, B.

    2015-09-01

    Infrared focal plane arrays (IRFPA) based on HgCdTe semiconductor alloys have been shown to be ideal for tactical and strategic applications. High density (>1 M pixel), high operability HgCdTe detectors on large area, low-cost composite substrates, such as CdTe-buffered Si or GaAs, are envisioned for next-generation IRFPAs. Thermal expansion mismatch is among various material parameters that govern the structural properties of the final detector layer. It has previously been shown that thermal expansion mismatch plays the dominant role in the residual stress characteristics of these heteroepitaxial structures (Jacobs et al. in J Electron Mater 37:1480, 2008). The wafer curvature (bowing) resulting from residual stress, is a likely source of problems that may occur during subsequent processing. This includes cracking of the film and substrate during post-growth annealing processes or even certain characterization techniques. In this work, we examine dynamic curvature and stress during molecular beam epitaxy (MBE), of CdTe on Si and GaAs substrates. The effect of temperature changes on wafer curvature throughout the growth sequence is documented using a multi-beam optical sensor developed by K-Space Associates. This monitoring technique makes possible the study of growth sequences which employ annealing schemes and/or interlayers to influence the final residual stress state of the heteroepitaxial structures.

  17. Microstructures of InN film on 4H-SiC (0001) substrate grown by RF-MBE

    NASA Astrophysics Data System (ADS)

    Jantawongrit, P.; Sanorpim, S.; Yaguchi, H.; Orihara, M.; Limsuwan, P.

    2015-08-01

    InN film was grown on 4H-SiC (0001) substrate by RF plasma-assisted molecular beam epitaxy (RF-MBE). Prior to the growth of InN film, an InN buffer layer with a thickness of ∼5.5 nm was grown on the substrate. Surface morphology, microstructure and structural quality of InN film were investigated. Micro-structural defects, such as stacking faults and anti-phase domain in InN film were carefully investigated using transmission electron microscopy (TEM). The results show that a high density of line contrasts, parallel to the growth direction (c-axis), was clearly observed in the grown InN film. Dark field TEM images recorded with diffraction vectors g=11\\bar{2}0 and g = 0002 revealed that such line contrasts evolved from a coalescence of the adjacent misoriented islands during the initial stage of the InN nucleation on the substrate surface. This InN nucleation also led to a generation of anti-phase domains. Project supported by the Thailand Center of Excellence in Physics (ThEP) and the King Mongkut's University of Technology Thonburi under The National Research University Project. One of the authors (S. Sanorpim) was supported by the National Research Council of Thailand (NRCT) and the Thai Government Stimulus Package 2 (TKK2555), under the Project for Establishment of Comprehensive Center for Innovative Food, Health Products and Agriculture.

  18. Surface sulfurization on MBE-grown Cu(In1-x,Gax)Se2 thin films and devices

    NASA Astrophysics Data System (ADS)

    Khatri, Ishwor; Matsuyama, Isamu; Yamaguchi, Hiroshi; Fukai, Hirofumi; Nakada, Tokio

    2015-08-01

    Molecular beam epitaxy (MBE) grown Cu(In1-x,Gax)Se2 (CIGS) thin films were sulfurized at temperatures of 450-550 °C for 30 min in a 10% H2S-N2 mixture gas. The micro-roughness together with the S diffusion in the CIGS surfaces increased with increasing sulfurization temperature. Both near-band-edge PL intensity and decay time of the CIGS absorber layer enhanced after sulfurization. PL sub-peak around 80 meV below the main peak almost disappeared after sulfurization above 500 °C, which is expected due to the occupation of Se vacancies (Vse) with S. The open-circuit voltage (Voc), hence conversion efficiency, improved after sulfurization. The photovoltaic performance of the solar cells was consistent with PL intensity. Moreover, it is found for the first time from the SIMS analysis that the Cu atoms were depleted at the surface of CIGS layer after sulfurization, which could result in the improved Voc.

  19. Ordered growth of topological insulator Bi2Se3 thin films on dielectric amorphous SiO2 by MBE.

    PubMed

    Jerng, Sahng-Kyoon; Joo, Kisu; Kim, Youngwook; Yoon, Sang-Moon; Lee, Jae Hong; Kim, Miyoung; Kim, Jun Sung; Yoon, Euijoon; Chun, Seung-Hyun; Kim, Yong Seung

    2013-11-01

    Topological insulators (TIs) are exotic materials which have topologically protected states on the surface due to strong spin-orbit coupling. However, a lack of ordered growth of TI thin films on amorphous dielectrics and/or insulators presents a challenge for applications of TI-junctions. We report the growth of topological insulator Bi2Se3 thin films on amorphous SiO2 by molecular beam epitaxy (MBE). To achieve the ordered growth of Bi2Se3 on an amorphous surface, the formation of other phases at the interface is suppressed by Se passivation. Structural characterizations reveal that Bi2Se3 films are grown along the [001] direction with a good periodicity by the van der Waals epitaxy mechanism. A weak anti-localization effect of Bi2Se3 films grown on amorphous SiO2 shows a modulated electrical property by the gating response. Our approach for ordered growth of Bi2Se3 on an amorphous dielectric surface presents considerable advantages for TI-junctions with amorphous insulator or dielectric thin films.

  20. In Memory of Dorothy Heathcote, MBE (29 August 1926 to 8 October 2011)

    ERIC Educational Resources Information Center

    Saxton, Juliana; Miller, Carole

    2012-01-01

    In this article, the authors aim to provide a multifaceted lens on to Dorothy Heathcote's enormous influence on the field of drama education. They choose to order the reminiscences historically, focusing on Heathcote's consistency of passion and purpose. The anecdotes, lesson descriptions, and reminiscences capture her voice, her energy, and her…

  1. Surface defect states in MBE-grown CdTe layers

    SciTech Connect

    Olender, Karolina; Wosinski, Tadeusz; Fronc, Krzysztof; Tkaczyk, Zbigniew; Chusnutdinow, Sergij; Karczewski, Grzegorz

    2014-02-21

    Semiconductor surface plays an important role in the technology of semiconductor devices. In the present work we report results of our deep-level transient spectroscopy (DLTS) investigations of surface defect states in nitrogen doped p-type CdTe layers grown by the molecular-beam epitaxy technique. We observed a deep-level trap associated with surface states, with the activation energy for hole emission of 0.33 eV. DLTS peak position in the spectra for this trap, and its ionization energy, strongly depend on the electric field. Our measurements allow to determine a mechanism responsible for the enhancement of hole emission rate from the traps as the phonon-assisted tunnel effect. Density of surface defect states significantly decreased as a result of passivation in ammonium sulfide. Capacitance-voltage measurements confirmed the results obtained by the DLTS technique.

  2. Optical properties of ZnxMg1-xSe/GaAs heterojunctions grown by MBE

    NASA Astrophysics Data System (ADS)

    Bala, Waclaw; Glowacki, Grzegorz; Gapinski, Adam

    1997-06-01

    This works focuses on the study of optical properties of ZnxMg1-xSe epilayers grown by molecular beam epitaxy on n-type (001) GaAs substrates. Luminescence, reflectivity and Raman spectroscopy are studied. Photoluminescence spectra of the samples are dominated by blue emission bands, which can be associated with radiative recombination of free excitons. The reflectivity spectra were used to investigate the refractive index value and the thickness of the layers. Moreover the temperature dependence of the band-gap energy of ZnxMg1-xSe epilayers was determined. Using Raman spectroscopy we can obtain information about two kinds of longitudinal optical phonon modes observed at room temperature, whose frequencies and intensities depend characteristically on Mg content.

  3. High Resolution X-ray Diffraction Studies of MBE-Grown HgCdTe Layers on Bulk-Grown CdZnTe Substrate

    NASA Astrophysics Data System (ADS)

    Amarasinghe, Priyanthi M.; Qadri, Syed B.; Wijewarnasuriya, Priyalal S.

    2015-08-01

    The structural properties of molecular beam epitaxially (MBE)-grown Hg1- x Cd x Te epilayers on CdZnTe (211) substrate have been investigated using high-resolution x-ray topography and rocking curves. High-resolution x-ray diffraction 2 θ- θ scans of (422) reflections were utilized in calculating the out-of-plane lattice parameters of the HgCdTe layer and the CdZnTe substrate. The lattice strain of the HgCdTe layer was evaluated using the in-plane measurements of the (311) reflection. Etching seemed to improve the surface of the substrate by removing any damage caused by polishing or any post-processing. In spite of some localized line dislocations, a remarkable quality of the MBE-grown HgCdTe layer was observed. The full width at half maximum values of the HgCdTe layer and the CdZnTe substrate were determined as 43 arc-s and 16.2 arc-s, respectively.

  4. Investigation of p-side contact layers for II-VI compound semiconductor optical devices fabricated on InP substrates by MBE

    NASA Astrophysics Data System (ADS)

    Takamatsu, Shingo; Nomura, Ichirou; Shiraishi, Tomohiro; Kishino, Katsumi

    2015-09-01

    N-doped p-type ZnTe and ZnSeTe contact layers were investigated to evaluate which is more suitable for use in II-VI compound semiconductor optical devices on InP substrates. Contact resistances (Rc) between the contact layers and several electrode materials (Pd/Pt/Au, Pd/Au, and Au) were measured by the circular transmission line model (c-TLM) method using p-n diode samples grown on InP substrates by molecular beam epitaxy (MBE). The lowest Rc (6.5×10-5 Ω cm2) was obtained in the case of the ZnTe contact and Pd/Pt/Au electrode combination, which proves that the combination is suitable for obtaining low Rc. Yellow light-emitting diode devices with a ZnTe and ZnSeTe p-contact layer were fabricated by MBE to investigate the effect of different contact layers. The devices were characterized under direct current injections at room temperature. Yellow emission at around 600 nm was observed for each device. Higher emission intensity and lower slope resistance were obtained for the device with the ZnTe contact layer and Pd/Pt/Au electrode compared with other devices. These device performances are ascribed to the low Rc of the ZnTe contact and Pd/Pt/Au electrode combination.

  5. In-situ microscopic observation of GaAs surfaces during molecular beam epitaxy and metalorganic molecular beam epitaxy by scanning microprobe reflection high energy electron diffraction

    NASA Astrophysics Data System (ADS)

    Isu, Toshiro; Watanabe, Akiyoshi; Hata, Masayuki; Katayama, Yoshifumi

    1990-03-01

    Microscopic observations of epitaxial growth layers of GaAs were made with a scanning microprobe reflection high energy electron diffraction (RHEED). A scanning microprobe electron gun has been combined with a specially designed molecular beam epitaxy (MBE) system with both solid sources and gas sources. Scanning reflection electron microscope (SREM) images using the specular beam spot revealed granular features over the entire surfaces of MBE-grown GaAs layers, which were thought to come from undulation of the surface. Similar features of the surface were observed on the layers grown by gas-source MBE using trimethylgallium and arsine. A microscopic surface morphology was found to be fairly rough and the features depended on the species of the sources and growth conditions.

  6. Convergence of the Many-Body Expansion for Energy and Forces for Classical Polarizable Models in the Condensed Phase.

    PubMed

    Demerdash, Omar; Head-Gordon, Teresa

    2016-08-01

    We analyze convergence of energies and forces for the AMOEBA classical polarizable model when evaluated as a many-body expansion (MBE) against the corresponding N-body parent potential in the context of a condensed-phase water simulation. This is in contrast to most MBE formulations based on quantum mechanics, which focus only on convergence of energies for gas-phase clusters. Using a single water molecule as a definition of a body, we find that truncation of the MBE at third order, 3-AMOEBA, captures direct polarization exactly and yields apparent good convergence of the mutual polarization energy. However, it renders large errors in the magnitude of polarization forces and requires at least fourth-order terms in the MBE to converge toward the parent potential gradient values. We can improve the convergence of polarization forces for 3-AMOEBA by embedding the polarization response of dimers and trimers within a complete representation of the fixed electrostatics of the entire system. We show that the electrostatic embedding formalism helps identify the specific configurations involving linear hydrogen-bonding arrangements that are poorly convergent at the 3-body level. By extending the definition of a body to be a large water cluster, we can reduce errors in forces to yield an approximate polarization model that is up to 10 times faster than the parent potential. The 3-AMOEBA model offers new ways to investigate how the properties of bulk water depend on the degree of connectivity in the liquid. PMID:27405002

  7. Intrinsic and interfacial recombination in OMVPE- and MBE-prepared GaAs/Al[sub x]Ga[sub 1-x]As heterostructures

    SciTech Connect

    Gilliland, G.D.; Wolford, D.J.; Kuech, T.F.; Bradley, J.A. . Thomas J. Watson Research Center); Klem, J.; Hjalmarson, H.P. )

    1993-01-01

    We have studied intrinsic free-carrier recombination in a variety of GaAs structures, including: OMVPE- and MBE-prepared GaAs/Al[sub x]Ga[sub 1-x]As double heterostructures, Na[sub 2]S passivated GaAs structures and bare GaAs structures. We find OMVPE prepared structures are superior to all of these other structures with 300 K lifetimes of [approximately] 2.5 [mu]s and negligible nonradiative interface and bulkrecombination, and thus are truly surface-free (S < 40 cm/s). Moreover, we observe systematic trends in optical properties versus growth conditions. Lastly, we find that the presence of free-exciton recombination in the low-temperature photoluminescence spectra is a necessary but not sufficient condition for optimal optical properties (i.e. long minority-carrier lifetimes).

  8. Characterization of vertical Au/β-Ga2O3 single-crystal Schottky photodiodes with MBE-grown high-resistivity epitaxial layer

    NASA Astrophysics Data System (ADS)

    X, Z. Liu; C, Yue; C, T. Xia; W, L. Zhang

    2016-01-01

    High-resistivity β-Ga2O3 thin films were grown on Si-doped n-type conductive β-Ga2O3 single crystals by molecular beam epitaxy (MBE). Vertical-type Schottky diodes were fabricated, and the electrical properties of the Schottky diodes were studied in this letter. The ideality factor and the series resistance of the Schottky diodes were estimated to be about 1.4 and 4.6× 106 Ω. The ionized donor concentration and the spreading voltage in the Schottky diodes region are about 4 × 1018 cm-3 and 7.6 V, respectively. The ultra-violet (UV) photo-sensitivity of the Schottky diodes was demonstrated by a low-pressure mercury lamp illumination. A photoresponsivity of 1.8 A/W and an external quantum efficiency of 8.7 × 102% were observed at forward bias voltage of 3.8 V, the proper driving voltage of read-out integrated circuit for UV camera. The gain of the Schottky diode was attributed to the existence of a potential barrier in the i-n junction between the MBE-grown highly resistive β-Ga2O3 thin films and the n-type conductive β-Ga2O3 single-crystal substrate. Project supported by the National Nature Science Foundation of China (Grant No. 61223002) the Science and Technology Commission of Shanghai Municipality, China (Grant No. 13111103700), and the Specialized Research Fund for the Doctoral Program of Higher Education of China (Grant No. 2012018530003).

  9. Multi-step interrupted-growth MBE technology for GaAs/AlGaAs (˜9.4 μm) room temperature operating quantum-cascade lasers

    NASA Astrophysics Data System (ADS)

    Kosiel, K.; Kubacka-Traczyk, J.; Sankowska, I.; Szerling, A.; Gutowski, P.; Bugajski, M.

    2012-09-01

    In order to adjust the highly controllable and optimum growth conditions, the multi-step interrupted-growth MBE processes were performed to deposit a series of GaAs/Al0.45Ga0.55As QCL structures. The additional calibrations of MBE system were carried out during the designed growth interruptions. This solution was combined with a relatively low growth rate of active region layers, in order to suppress the negative effects of elemental flux instabilities. As a result, the fabricated QCL structures have yielded devices operating with peak optical power of ˜12 mW at room temperature. That is a better result than was obtained for comparable structures deposited with a growth rate kept constant, and with the only initial calibrations performed just before the epitaxy of the overall structure.

  10. Spectroscopic determination of the bandgap crossover composition in MBE-grown AlxGa1-xAs

    DOE PAGES

    Fluegel, Brian; Alberi, Kirstin; Reno, John; Mascarenhas, Angelo

    2015-03-12

    The aluminum concentration dependence of the energies of the direct and indirect bandgaps arising from the Γ and X conduction bands are measured at 1.7 K in the semiconductor alloy AlxGa1-xAs. The composition at which the bands cross is determined from photoluminescence of molecular-beam epitaxy samples grown very close to crossover. The use of resonant laser excitation and the improved sample linewidth allows precise determination of the bound exciton transition energies. Moreover, photoluminescence excitation spectroscopy is used to measure the binding energies of the donor-bound excitons and the Γ free exciton binding energy.

  11. Lattice-engineered MBE growth of high-indium mole fraction InGaAs for low cost MMICs and (1.3--1.55 {micro}m) OEICs

    SciTech Connect

    Childs, T.T.; Sokolov, V.; Sullivan, C.T.

    1997-11-01

    Using molecular beam epitaxy (MBE) and lattice engineering techniques, the feasibility of combining photonic devices applicable to the 1.3 to 1.55 {micro}m wavelength range and monolithic microwave (or mm-wave) integrated circuits (MMICs) on GaAs is demonstrated. A key factor in the MBE growth is incorporation of an InGaAs active layer having an indium arsenide mole fraction of 0.35 or greater and its lattice compatibility with the underlying semi-insulating GaAs substrate. The InGaAs layer used for the photonic devices, can also serve as the active channel for the high electron mobility transistors (HEMTs) for application in MMICs. Several examples of active and passive photonic devices grown by MBE are presented including an optical ridge waveguide, and a photodetector for detection of light in the 1.3 {micro}m range. The material structure includes a 3-layer AlGaAs/GaAs/AlGaAs optical waveguide and a thin InGaAs absorbing layer situated directly above the optical waveguide. Metal-semiconductor-metal (MSM) photodetectors are formed on the top surface of the InGaAs layer for collection of the photo-induced carriers. The optical ridge waveguide is designed for lateral incidence of the light to enhance the MSM photodetector responsivity. Initial measurements on the optical waveguide and photodetector are presented.

  12. Use of a High-flux Atomic Oxygen Source for MBE growth of the di- and tri- oxides of Cr, Mo, and W

    NASA Astrophysics Data System (ADS)

    Ingle, Nicholas; Hammond, Robert; Beasley, Malcolm

    2000-03-01

    The MBE growth of several of the highly oxidized phases of the Group IIB elements (Cr, Mo, and W) are of great current interest. In particular, CrO_2, a theorized half-metallic ferromagnet, has yet to be grown in a form that allows high quality tunneling measurements to be performed. Also, thin films of WO3 for controlled Na doping studies are of interest to help understand the recently published results on possible superconductivity in this material(S. Reich and Y. Tsabba, EUROPEAN PHYSICAL JOURNAL B v. 9(1) pp. 1-4 MAY 1999 and Shengelaya A, Reich S, Tsabba Y, and Muller KA EUROPEAN PHYSICAL JOURNAL B , v. 12(1) pp. 13-15 NOV 1999). Using a new high-flux atomic oxygen source and detection scheme, RHEED, and in-situ core-level photoemission we present the atomic oxygen-temperature phase diagrams indicating the conditions under which the di- and tri- oxide phases of Cr, Mo, and W can be grown.

  13. X-ray magnetic spectroscopy of MBE-grown Mn-doped Bi{sub 2}Se{sub 3} thin films

    SciTech Connect

    Collins-McIntyre, L. J.; Watson, M. D.; Zhang, S. L.; Coldea, A. I.; Hesjedal, T.; Baker, A. A.; Harrison, S. E.; Pushp, A.; Kellock, A. J.; Parkin, S. S. P.; Laan, G. van der

    2014-12-15

    We report the growth of Mn-doped Bi{sub 2}Se{sub 3} thin films by molecular beam epitaxy (MBE), investigated by x-ray diffraction (XRD), atomic force microscopy (AFM), SQUID magnetometry and x-ray magnetic circular dichroism (XMCD). Epitaxial films were deposited on c-plane sapphire substrates by co-evaporation. The films exhibit a spiral growth mechanism typical of this material class, as revealed by AFM. The XRD measurements demonstrate a good crystalline structure which is retained upon doping up to ∼7.5 atomic-% Mn, determined by Rutherford backscattering spectrometry (RBS), and show no evidence of the formation of parasitic phases. However an increasing interstitial incorporation of Mn is observed with increasing doping concentration. A magnetic moment of 5.1 μ{sub B}/Mn is obtained from bulk-sensitive SQUID measurements, and a much lower moment of 1.6 μ{sub B}/Mn from surface-sensitive XMCD. At ∼2.5 K, XMCD at the Mn L{sub 2,3} edge, reveals short-range magnetic order in the films and indicates ferromagnetic order below 1.5 K.

  14. The long noncoding RNAs PVT1 and uc002mbe.2 in sera provide a new supplementary method for hepatocellular carcinoma diagnosis

    PubMed Central

    Yu, Jinyu; Han, Junqing; Zhang, Jian; Li, Guanzhen; Liu, Hui; Cui, Xianping; Xu, Yantian; Li, Tao; Liu, Juan; Wang, Chuanxi

    2016-01-01

    Abstract Hepatocellular carcinoma (HCC) is the most common primary malignancy of the liver in adults worldwide. Several studies have demonstrated that long noncoding RNAs (lncRNAs) are involved in the development of various types of cancer, including HCC. These findings prompted us to examine the detectability of lncRNAs in blood samples from patients with HCC. In this study, we explored the expression levels of 31 cancer-related lncRNAs in sera from 71 HCC patients and 64 healthy individuals by reverse transcription and quantitative polymerase chain reaction (RT-qPCR). We found that 25 lncRNAs could be detected in the serum and that 7 had significantly different expression levels. A 2-lncRNA signature (PVT1 and uc002mbe.2) identified by stepwise regression showed potential as a diagnostic marker for HCC. The area under the receiver operating characteristic (ROC) curve was 0.764 (95% CI: 0.684–0.833). The sensitivity and specificity values of this serum 2-lncRNA signature for distinguishing HCC patients from the healthy group were 60.56% and 90.62%, respectively. The diagnostic ability of the combination of the serum 2-lncRNA signature with alpha-fetoprotein (AFP) was much greater than that of AFP alone. The expression levels of the 2 lncRNAs were associated with clinical parameters including tumor size, Barcelona Clinic Liver Cancer (BCLC) stage, and serum bilirubin. PMID:27495068

  15. The impact of RF-plasma power in carrier relaxation dynamics of unintentional doped GaN epitaxial layers grown by MBE

    NASA Astrophysics Data System (ADS)

    Prakash, Nisha; Anand, Kritika; Barvat, Arun; Pal, Prabir; Singh, Dilip K.; Jewariya, Mukesh; Ragam, Srinivasa; Adhikari, Sonachand; Maurya, Kamlesh K.; Khanna, Suraj P.

    2016-04-01

    In this work, unintentionally doped GaN samples were prepared on GaN template by radio frequency (RF)-plasma MBE technique using two different RF-plasma powers. Photoluminescence (PL), steady state photoconductivity (PC) and ultrafast optical pump-probe spectroscopy measurements have been carried out to characterize the samples. The effect of RF-plasma power towards unintentional doping and giving rise to yellow luminescence (YL) is discussed. Our PC measurements show relatively faster decay for sample grown with higher RF-plasma power. In addition, the ultrafast optical pump-probe spectroscopy results show the presence of various defect levels with different relaxation times. A faster ultrafast relaxation time from the conduction band to the closest defect level and conduction band to the next defect level was observed for the sample grown with higher plasma power. A comparatively low defect density and faster carrier relaxation observed in higher RF-plasma power grown samples is caused by lower impurities and gallium vacancies. The results imply that RF-plasma power is very important parameter for the growth of epitaxial GaN films and undesirable impurities and gallium vacancies might get incorporated in the epitaxial GaN films.

  16. The long noncoding RNAs PVT1 and uc002mbe.2 in sera provide a new supplementary method for hepatocellular carcinoma diagnosis.

    PubMed

    Yu, Jinyu; Han, Junqing; Zhang, Jian; Li, Guanzhen; Liu, Hui; Cui, Xianping; Xu, Yantian; Li, Tao; Liu, Juan; Wang, Chuanxi

    2016-08-01

    Hepatocellular carcinoma (HCC) is the most common primary malignancy of the liver in adults worldwide. Several studies have demonstrated that long noncoding RNAs (lncRNAs) are involved in the development of various types of cancer, including HCC. These findings prompted us to examine the detectability of lncRNAs in blood samples from patients with HCC. In this study, we explored the expression levels of 31 cancer-related lncRNAs in sera from 71 HCC patients and 64 healthy individuals by reverse transcription and quantitative polymerase chain reaction (RT-qPCR). We found that 25 lncRNAs could be detected in the serum and that 7 had significantly different expression levels. A 2-lncRNA signature (PVT1 and uc002mbe.2) identified by stepwise regression showed potential as a diagnostic marker for HCC. The area under the receiver operating characteristic (ROC) curve was 0.764 (95% CI: 0.684-0.833). The sensitivity and specificity values of this serum 2-lncRNA signature for distinguishing HCC patients from the healthy group were 60.56% and 90.62%, respectively. The diagnostic ability of the combination of the serum 2-lncRNA signature with alpha-fetoprotein (AFP) was much greater than that of AFP alone. The expression levels of the 2 lncRNAs were associated with clinical parameters including tumor size, Barcelona Clinic Liver Cancer (BCLC) stage, and serum bilirubin. PMID:27495068

  17. The MBE growth and optical quality of BaTiO{sub 3} and SrTiO{sub 3} thin films on MgO

    SciTech Connect

    McKee, R.A.; Specht, E.D.; Alexander, K.B.; Walker, F.J.

    1994-05-01

    High quality epitaxial BaTiO{sub 3} and SrTiO{sub 3} have been grown on MgO; stabilized at a one unit cell height; and grown to film thicknesses of 0.5--0.7 {mu}m. These relatively thick films remain adherent when thermally cycled between growth temperatures and room temperature, are crack free with high optical quality, and have both in-plane and out-of-plane X-ray rocking curves of 0.3--0.5{degree}. These films have been grown using molecular beam epitaxy (MBE) methods starting with the TiO{sub 2} layer of the perovskite structure. The TiO{sub 2}-layer/MgO interface uniquely satisfies electrostatic requirements for perovskite heteroepitaxy and provides the template structure that leads to the high quality films that are obtained. Wavelength dependence of optical loss has been characterized between 475 nm and 705 nm with loss coefficients < l dB/cm being obtained at the He-Ne wavelength.

  18. Contribution of generation-recombination processes at inner interface of MBE-grown Hg1-xCdxTe heterostucture to dark current of small active area photodiode

    NASA Astrophysics Data System (ADS)

    Chekanova, Galina V.; Drugova, Albina A.; Kholodnov, Viacheslav; Nikitin, Mikhail S.

    2009-09-01

    Multilayer heterostructures of Hg1-xCdxTe alloy grown by Molecular Beam Epitaxy (MBE) on large size alternative substrates Si, GaAs and Ge are considered as one of productive alternative materials for issue of large format photovoltaic (PV) infrared (IR) focal plane arrays. However reaching of ultimate performance of small-pitched photodiode's (PD) covering spectral range from 8 to 12 μm depends on electronic properties of both individual layers and heterostructure interfaces. Due to small thickness of heterostructure layers, interfaces are located close to active regions of p-n junction and hence generation-recombination processes at interfaces will contribute to value of current flowing through junction. As usual measured dark current value of small-sized PD is higher than estimated from calculation and cannot be explained by discrepancy between real and estimated charge carriers concentration in absorption layers where p-n junction is formed. Objective of the present work was to calculate the contribution of recombination of charge carriers via electronic states on nearby inner interface to dark current of Hg1-xCdxTe LWIR PD (λco equals to 9.5-10.3 μm at Top=77 K) and its variation with absorption layer parameters and compare it to measured data on small-pitched arrays. We have concluded previously that at high recombination rate dark current can grow in orders of value.

  19. Comprehensive strain and band gap analysis of PA-MBE grown AlGaN/GaN heterostructures on sapphire with ultra thin buffer

    SciTech Connect

    Mahata, Mihir Kumar; Ghosh, Saptarsi; Jana, Sanjay Kumar; Bag, Ankush; Kumar, Rahul; Chakraborty, Apurba; Biswas, Dhrubes; Mukhopadhyay, Partha

    2014-11-15

    In this work, cluster tool (CT) Plasma Assisted Molecular Beam Epitaxy (PA-MBE) grown AlGaN/GaN heterostructure on c-plane (0 0 0 1) sapphire (Al{sub 2}O{sub 3}) were investigated by High Resolution X-ray Diffraction (HRXRD), Room Temperature Raman Spectroscopy (RTRS), and Room Temperature Photoluminescence (RTPL). The effects of strain and doping on GaN and AlGaN layers were investigated thoroughly. The out-of-plane (‘c’) and in-plane (‘a’) lattice parameters were measured from RTRS analysis and as well as reciprocal space mapping (RSM) from HRXRD scan of (002) and (105) plane. The in-plane (out-of plane) strain of the samples were found to be −2.5 × 10{sup −3}(1 × 10{sup −3}), and −1.7 × 10{sup −3}(2 × 10{sup −3}) in GaN layer and 5.1 × 10{sup −3} (−3.3 × 10{sup −3}), and 8.8 × 10{sup −3}(−1.3 × 10{sup −3}) in AlGaN layer, respectively. In addition, the band structures of AlGaN/GaN interface were estimated by both theoretical (based on elastic theory) and experimental observations of the RTPL spectrum.

  20. The characteristics of MBE-grown InxAl1-xN/GaN surface states

    NASA Astrophysics Data System (ADS)

    Jiao, Wenyuan; Kong, Wei; Li, Jincheng; Collar, Kristen; Kim, Tong-Ho; Losurdo, Maria; Brown, April S.

    2016-08-01

    The density and energy distribution of InxAl1-xN/GaN surface donor states are studied for InxAl1-xN structures with varying indium compositions. The results support a surface states model with a constant energy distribution of 2.17-2.63 eV below the conduction band minimum and a concentration of 4.64-8.27 × 1013 cm-2 eV-1. It is shown that the properties of the surface states are affected by the surface indium composition xs, as opposed to the bulk composition, xb (InxAl1-xN). Higher surface indium composition xs increases the density of surface states and narrows their energy distribution.

  1. Structural, electronic, and magnetic investigation of magnetic ordering in MBE-grown CrxSb2-xTe3 thin films

    NASA Astrophysics Data System (ADS)

    Collins-McIntyre, L. J.; Duffy, L. B.; Singh, A.; Steinke, N.-J.; Kinane, C. J.; Charlton, T. R.; Pushp, A.; Kellock, A. J.; Parkin, S. S. P.; Holmes, S. N.; Barnes, C. H. W.; van der Laan, G.; Langridge, S.; Hesjedal, T.

    2016-07-01

    We report the structural, electronic, and magnetic study of Cr-doped Sb2Te3 thin films grown by a two-step deposition process using molecular-beam epitaxy (MBE). The samples were investigated using a variety of complementary techniques, namely, x-ray diffraction (XRD), atomic force microscopy, SQUID magnetometry, magneto-transport, and polarized neutron reflectometry (PNR). It is found that the samples retain good crystalline order up to a doping level of x=0.42 (in Cr x Sb2-x Te3), above which degradation of the crystal structure is observed by XRD. Fits to the recorded XRD spectra indicate a general reduction in the c-axis lattice parameter as a function of doping, consistent with substitutional doping with an ion of smaller ionic radius. The samples show soft ferromagnetic behavior with the easy axis of magnetization being out-of-plane. The saturation magnetization is dependent on the doping level, and reaches from ˜2 μ_\\text{B} to almost 3 μ_\\text{B} per Cr ion. The transition temperature (T{c}) depends strongly on the Cr concentration and is found to increase with doping concentration. For the highest achievable doping level for phase-pure films of x=0.42 , a T{c} of 125 K was determined. Electric transport measurements find surface-dominated transport below ˜10 K. The magnetic properties extracted from anomalous Hall effect data are in excellent agreement with the magnetometry data. PNR studies indicate a uniform magnetization profile throughout the film, with no indication of enhanced magnetic order towards the sample surface.

  2. Structural, electronic, and magnetic investigation of magnetic ordering in MBE-grown CrxSb2‑xTe3 thin films

    NASA Astrophysics Data System (ADS)

    Collins-McIntyre, L. J.; Duffy, L. B.; Singh, A.; Steinke, N.-J.; Kinane, C. J.; Charlton, T. R.; Pushp, A.; Kellock, A. J.; Parkin, S. S. P.; Holmes, S. N.; Barnes, C. H. W.; van der Laan, G.; Langridge, S.; Hesjedal, T.

    2016-07-01

    We report the structural, electronic, and magnetic study of Cr-doped Sb2Te3 thin films grown by a two-step deposition process using molecular-beam epitaxy (MBE). The samples were investigated using a variety of complementary techniques, namely, x-ray diffraction (XRD), atomic force microscopy, SQUID magnetometry, magneto-transport, and polarized neutron reflectometry (PNR). It is found that the samples retain good crystalline order up to a doping level of x=0.42 (in Cr x Sb2‑x Te3), above which degradation of the crystal structure is observed by XRD. Fits to the recorded XRD spectra indicate a general reduction in the c-axis lattice parameter as a function of doping, consistent with substitutional doping with an ion of smaller ionic radius. The samples show soft ferromagnetic behavior with the easy axis of magnetization being out-of-plane. The saturation magnetization is dependent on the doping level, and reaches from ∼2 μ_\\text{B} to almost 3 μ_\\text{B} per Cr ion. The transition temperature (T{c}) depends strongly on the Cr concentration and is found to increase with doping concentration. For the highest achievable doping level for phase-pure films of x=0.42 , a T{c} of 125 K was determined. Electric transport measurements find surface-dominated transport below ∼10 K. The magnetic properties extracted from anomalous Hall effect data are in excellent agreement with the magnetometry data. PNR studies indicate a uniform magnetization profile throughout the film, with no indication of enhanced magnetic order towards the sample surface.

  3. Formation and Temperature Effect of InN Nanodots by PA-MBE via Droplet Epitaxy Technique

    NASA Astrophysics Data System (ADS)

    Chen, Hugo Juin-Yu; Yang, Dian-Long; Huang, Tseh-Wet; Yu, Ing-Song

    2016-05-01

    In this report, self-organized indium nitride nanodots have been grown on Si (111) by droplet epitaxy method and their density can reach as high as 2.83 × 1011 cm-2 for the growth at low temperature of 250 °C. Based on the in situ reflection high-energy electron diffraction, the surface condition, indium droplets, and the formation of InN nanodots are identified during the epitaxy. The X-ray photoelectron spectroscopy and photoluminescence measurements have shown the formation of InN nanodots as well. The growth mechanism of InN nanodots could be described via the characterizations of indium droplets and InN nanodots using scanning electron microscopy, atomic force microscopy, and transmission electron microscopy. The density of the InN nanodots was less than that of the In droplets due to the surface diffusion and desorption of atoms during the nitridation and annealing process. The average size and density of InN nanodots can be controlled by the substrate temperatures during the growth. For the growth at lower temperature, we obtained the higher density and smaller average size of InN nanodots. To minimize the total surface energy, the coarsening and some preferred orientations of InN nanodots were observed for the growth at high temperature.

  4. Helicon Discharge with Selectable Nitrogen Reactive Species Production as a Plasma Source for III-group Nitrides Growth by MBE

    NASA Astrophysics Data System (ADS)

    Biloiu, Costel; Doss, Forest; Scime, Earl

    2004-11-01

    Plasma assisted molecular beam epitaxy (PAMBE) of III-N materials is a potential alternative to MOCVD for fabrication of high quality wide band gap semiconductor devices. In the helicon plasma source, it may be possible to control the population of specific reactive nitrogen species by modification of the electron energy distribution function through the resonant wave-particle interaction arising from electrons traveling at same velocity as the helicon wave phase velocity. We report preliminary results on control of reactive nitrogen species performed in a steady state, high density, helicon plasma source CHEWIE (Compact HElicon Waves and Instabilities Experiment). The helicon vacuum chamber is a 12 cm long, Pyrex tube, 6 cm in diameter, connected to a stainless steel diffusion chamber. RF power of up to 1.0 kW over a frequency range of 3-28 MHz is used to create the steady state plasma. A 7 cm long, half wave, m = +1, helical antenna couples the rf energy into the plasma. A single solenoidal magnetic field coil surrounds the source and is capable of generating axial magnetic fields up to 600 G. Optical emission spectroscopy investigations show that under certain conditions, the decay from the long lived A^3Σ_u^+ state dominates the emission spectrum of the plasma.

  5. Room temperature mid-infrared InAsSbN multi-quantum well photodiodes grown by MBE

    NASA Astrophysics Data System (ADS)

    Kesaria, M.; de la Mare, M.; Krier, A.

    2016-11-01

    Room temperature photoresponse in the mid-infrared spectral region is demonstrated from InAsSbN/InAs multi-quantum well photodiodes grown by nitrogen plasma assisted molecular beam epitaxy. The structural quality of the InAsSbN MQWs was ascertained in situ by reflection high energy electron diffraction and ex situ by high resolution x-ray diffraction and photoluminescence measurements. The extended long wavelength photoresponse is identified to originate from the electron–heavy hole (e1–hh1) and electron–light hole (e1–lh1) transitions in the InAsSbN MQW, with a cut off wavelength ~4.20 µm and peak detectivity D *  =  1.25  ×  109 cm Hz1/2 W‑1.

  6. Study of InN nanorods growth mechanism using ultrathin Au layer by plasma-assisted MBE on Si(111)

    NASA Astrophysics Data System (ADS)

    Kumar, Mahesh; Rajpalke, Mohana K.; Roul, Basanta; Bhat, Thirumaleshwara N.; Krupanidhi, S. B.

    2014-01-01

    InN nanorods (NRs) were grown on Si(111) substrate by plasma-assisted molecular beam epitaxy. The growth of InN NRs has been demonstrated using an electron-beam evaporated (~2 nm) Au layer prior to the initiation of growth. The structure and morphology of as deposited Au film, annealed at 600 °C, and InN NRs were investigated using X-ray photoelectron spectroscopy and scanning electron microscopy. Chemical characterization was performed with energy dispersive X-ray analysis. Single-crystalline wurtzite structure of InN NRs is verified by transmission electron microscopy. The formation process of NRs is investigated and a qualitative mechanism is proposed.

  7. A review of MBE grown 0D, 1D and 2D quantum structures in a nanowire

    NASA Astrophysics Data System (ADS)

    de la Mata, Maria; Zhou, Xiang; Furtmayr, Florian; Teubert, Jörg; Gradecak, Silvija; Eickhoff, Martin; Fontcuberta i Morral, Anna; Arbiol, Jordi

    2013-05-01

    We review different strategies to achieve a three-dimensional energy bandgap modulation in a nanowire (NW) by the introduction of self-assembled 0D, 1D and 2D quantum structures, quantum dots (QDs), quantum wires (QWRs) and quantum wells (QWs). Starting with the well-known axial, radial (coaxial/prismatic) or polytypic quantum wells in GaN/AlN, GaAs/AlAs or wurtzite/zinc-blende systems, respectively, we move to more sophisticated structures by lowering their dimensionality. New recent approaches developed for the self-assembly of GaN quantum wires and InAs or AlGaAs quantum dots on single nanowire templates are reported and discussed. Aberration corrected scanning transmission electron microcopy is presented as a powerful tool to determine the structure and morphology at the atomic scale allowing for the creation of 3D atomic models that can help us to understand the enhanced optical properties of these advanced quantum structures.

  8. Bandedge optical properties of MBE grown GaAsBi films measured by photoluminescence and photothermal deflection spectroscopy

    NASA Astrophysics Data System (ADS)

    Beaudoin, M.; Lewis, R. B.; Andrews, J. J.; Bahrami-Yekta, V.; Masnadi-Shirazi, M.; O'Leary, S. K.; Tiedje, T.

    2015-09-01

    The bandedge optical properties of GaAsBi films, as thick as 470 nm, with Bi content varying from 0.7% Bi to 2.8% Bi grown by molecular beam epitaxy on GaAs substrates are measured by photoluminescence (PL) and photothermal deflection spectroscopy (PDS). The PDS spectra were fit with a modified Fernelius model which takes into account multiple reflections within the GaAsBi layer and GaAs substrate. Three undoped samples and two samples that are degenerately doped with silicon are studied. The undoped samples show a clear Urbach absorption edge with a composition dependent bandgap that decreases by 56 meV/% Bi and a composition independent Urbach slope parameter of 25 meV due to absorption by Bi cluster states near the valence band. The doped samples show a long absorption tail possibly due to absorption by gap states and free carriers in addition to a Burstein-Moss bandgap shift. PL of the undoped samples shows a lower energy emission peak due to defects not observed in the usually available thin samples (50 nm or less) grown under similar conditions.

  9. Doping of MBE grown cubic GaN on 3C-SiC (001) by CBr{sub 4}

    SciTech Connect

    Zado, A.; Tschumak, E.; Lischka, K.; As, D. J.; Gerlach, J. W.

    2010-11-01

    We report on carbon doping of cubic GaN by CBr{sub 4} using plasma-assisted molecular beam epitaxy on 3C-SiC (001) substrates. The samples consist of a 70 nm thick GaN buffer followed by a 550 nm thick GaN:C layer. Carbon doping is realized with a home-made carbon tetrabromide sublimation source. The CBr{sub 4} beam equivalent pressure was established by a needle valve and was varied between 2x10{sup -9} mbar and 6x10{sup -6} mbar. The growth was controlled by in-situ reflection high energy electron diffraction. The incorporated carbon concentration is obtained from secondary ion mass spectroscopy. Capacitance voltage characteristics were measured using metal-insulator-semiconductor structures. Capacitance voltage measurements on nominally undoped cubic GaN showed n-type conductivity with N{sub D}-N{sub A} = 1x10{sup 17} cm{sup -3}. With increasing CBr{sub 4} flux the conductivity type changes to p-type and for the highest CBr{sub 4} flux N{sub A}-N{sub D} = 4{center_dot}5x10{sup 18} cm{sup -3} was obtained.

  10. Formation of Metal-Semiconductor Interfaces on Mbe-Grown Gallium ARSENIDE(100): Surface Photovoltage, Chemistry and Band Bending

    NASA Astrophysics Data System (ADS)

    Mao, Duli

    1992-01-01

    The chemical, structural and electronic properties of the metal-GaAs interfaces formed on the polar (100) surface are studied using high resolution core level photoemission spectroscopy (PES) and low energy electron diffraction (LEED). The clean (4 x 2)-c(8 x 2) reconstructed GaAs(100) surface, prepared by molecular beam epitaxy and subsequent thermal decapping of an As protective layer, is characterized carefully. Ga 3d and As 3d core levels are analyzed using test square curve fitting. Two Ga surface components are resolved while only one surface component is necessary for As. The assignment of these surface components to different surface atomic arrangements is discussed. The surface Fermi level position with respect to the valence band maximum is also investigated as a function of decapping temperature. Metal (In, Ga, Au)/GaAs(100) interfaces, formed at both room (RT) and low temperature (LT), are studied. The morphology of these interfaces resembles that of metal/GaAs(110) interfaces formed at LT, in that the deposited metal atoms reside at the surface as isolated adatoms rather than as clusters at submonolayer coverage. Metal clustering is only important at coverages higher than a few monolayers and is more prominent at RT than at LT. The GaAs(100) band bending is studied as a function of metal coverage and deposition temperature. At submonolayer metal coverages, In and Ga both cause reduced band bending (~ 0.2eV) on n-type GaAs, a phenomenon similar to the Fermi level overshoot observed at LT-formed metal/p-GaAs(110) interfaces and indicative of formation of adatom-induced donor levels in the upper part of the band gap. With Au, In and Ga, the Fermi level is pinned at 0.4eV, 0.6eV and 0.68eV above the valence band maximum respectively, in good agreement with the results obtained at metal/GaAs(110) interfaces. This contradicts recent claims of near-Schottky limit for these interfaces. Evidence of correlation between pinning and overlayer metallization is

  11. Effects of MgO buffer annealing on optical and electrical quality of P-MBE grown ZnO films on c-sapphire

    NASA Astrophysics Data System (ADS)

    Setiawan, A.; Yao, T.

    2016-04-01

    Zinc oxide (ZnO) has been attracting much attention because of its potential applications in photonic and optoelectronic devices. In this present study, we investigated the effect of MgO buffer annealing on the optical and electrical quality of P-MBE grown ZnO films on c-sapphire with MgO buffer layer. The optical quality was observed by low-temperature PL (photoluminescence) measurement in the near band edge emission region measured at 10K and at 77K. The emission line located at 3.368eV dominates the spectrum in both samples (ZnO with and without MgO buffer annealing) at 10K and 77K. This emission can be divided into two peaks, 3.367eV and 3.363eV and assigned as I2 (ionized donor bound excitons emission) and I4 (Hydrogen donor related emission), respectively. The relative intensity of these donor bound exactions to free exaction emission of the sample without MgO buffer annealing is greater than that of the sample with MgO buffer annealing. Comparison of the PL spectra of ZnO with and without annealing revealed that the intensity of free exciton emission from the sample with MgO buffer annealing is twice of that from the sample without annealing. We also found that the intensity of deep-level broad emission is reduced by about 1/3 by MgO-buffer annealing. Hence, the decrease of deep level emission intensity and the increase of free exciton emission intensity by annealing of MgO buffer corresponds to the reduction of defects of the ZnO film. The PL properties also suggest that there are fewer nonradiative recombination centers in ZnO layers with MgO buffer annealing than those in ZnO layers grown without MgO buffer annealing. The electrical quality was measured by room temperature Hall measurements. We found that the samples have a background n-type carrier concentration. The ZnO samples with MgO buffer annealing has a carrier concentration of 1.17×1017 cm-3 and Hall mobility of 120 cm2/V.s, while the ZnO sample without MgO buffer annealing has a carrier

  12. Energy.

    ERIC Educational Resources Information Center

    Online-Offline, 1998

    1998-01-01

    This issue focuses on the theme of "Energy," and describes several educational resources (Web sites, CD-ROMs and software, videos, books, activities, and other resources). Sidebars offer features on alternative energy, animal energy, internal combustion engines, and energy from food. Subthemes include harnessing energy, human energy, and natural…

  13. Growth of carbon-doped base GaAs/AlGaAs HBT by gas-source MBE using TEG, TEA, TMG, AsH3, and Si2H6

    NASA Astrophysics Data System (ADS)

    Ando, Hideyasu; Fujii, Toshio; Sandhu, Adarsh; Takahashi, Tsuyoshi; Ishikawa, Hideaki; Okamoto, Naoya; Yokoyama, Naoki

    1992-05-01

    High-performance carbon-doped-base GaAs/AlGaAs heterobipolar transistors (HBTs) were grown by gas-source MBE using only gaseous sources including dopant sources. The AlGaAs emitter layer was doped with Si from uncracked SI2H6 and the base layer was doped with carbon from TMG. From SIMS analysis it was confirmed that a well-defined emitter-base junction with sharp carbon profile was obtained. The base-current ideality factor from the Gummel plot was 1.47, and the emitter-base junction ideality factor was 1.12. A high dc current gain of 53 was obtained at a current density of 4 x 10 exp 4 A/sq cm. The device characteristics of our carbon-doped HBTs were found to be stable under current stress.

  14. Infrared Photodiodes Made by Low Energy Ion Etching of Molecular Beam Epitaxy Grown Mercury-Cadmium Alloy

    NASA Astrophysics Data System (ADS)

    Yoo, Sung-Shik

    Ion etching was used to form junctions on the p-type (111)B Hg_{1-x}Cd_ {x}Te grown by Molecular Beam Epitaxy(MBE). When Hg_{1-x}Cd_{x}Te layers are etched by Ar ions at energies ranging between 300 and 450eV, the top Hg_{1 -x}Cd_{x}Te layer is converted to n-type. The converted region is electrically characterized as a defective n^+-region near the surface, and a low doped n^--region exist below the damaged region. The total thickness of the converted n-type layer was found to be considerable. These results suggest that the creation of the n-type layer is due to the filling of mercury vacancies by mercury atoms displaced by the Ar ion irradiation on the surface. For the performance of the resulting photodiodes on MBE grown (111)B Hg_{1-x}Cd _{x}Te using this technique, the dynamic resistances at 80K are one order of magnitude less than those of junctions made on Liquid Phase Epitaxially and Bulk grown Hg_{1 -x}Cd_{x}Te. The ion etching technique was compared with ion implantation technique by fabricating diodes on the same MBE grown (111)B Hg _{1-x}Cd_{x}Te layers. The result of the comparison illustrates that ion etching technique is as good as ion implantation technique for the fabrication of Hg_{1-x}Cd _{x}Te photodiodes. Also it is believed that the performance of the diodes is limited by a relatively large density of twin defects usually found in MBE grown (111)B Hg_{1-x}Cd _{x}Te.

  15. Molecular-beam epitaxy of monolayer and bilayer WSe2: a scanning tunneling microscopy/spectroscopy study and deduction of exciton binding energy

    NASA Astrophysics Data System (ADS)

    Liu, H. J.; Jiao, L.; Xie, L.; Yang, F.; Chen, J. L.; Ho, W. K.; Gao, C. L.; Jia, J. F.; Cui, X. D.; Xie, M. H.

    2015-09-01

    Interest in two-dimensional (2D) transition-metal dichalcogenides (TMDs) has prompted some recent efforts to grow ultrathin layers of these materials epitaxially using molecular-beam epitaxy (MBE). However, growths of monolayer (ML) and bilayer (BL) WSe2—an important member of the TMD family—by the MBE method remain uncharted, probably because of the difficulty in generating tungsten fluxes from the elemental source. In this work, we present a scanning tunneling microscopy and spectroscopy (STM/S) study of MBE-grown WSe2 ML and BL, showing atomically flat epifilm with no domain boundary (DB) defect. This contrasts epitaxial MoSe2 films grown by the same method, where a dense network of the DB defects is present. The STS measurements of ML and BL WSe2 domains of the same sample reveal not only the bandgap narrowing upon increasing the film thickness from ML to BL, but also a band-bending effect across the boundary (step) between ML and BL domains. This band-bending appears to be dictated by the edge states at steps of the BL islands. Finally, comparison is made between the STS-measured electronic bandgaps with the exciton emission energies measured by photoluminescence, and the exciton binding energies in ML and BL WSe2 (and MoSe2) are thus estimated.

  16. Spectroscopic determination of the bandgap crossover composition in MBE-grown AlxGa1-xAs

    SciTech Connect

    Fluegel, Brian; Alberi, Kirstin; Reno, John; Mascarenhas, Angelo

    2015-03-12

    The aluminum concentration dependence of the energies of the direct and indirect bandgaps arising from the Γ and X conduction bands are measured at 1.7 K in the semiconductor alloy AlxGa1-xAs. The composition at which the bands cross is determined from photoluminescence of molecular-beam epitaxy samples grown very close to crossover. The use of resonant laser excitation and the improved sample linewidth allows precise determination of the bound exciton transition energies. Moreover, photoluminescence excitation spectroscopy is used to measure the binding energies of the donor-bound excitons and the Γ free exciton binding energy.

  17. Capping and decapping of MBE grown GaAs(001), Al 0.5Ga 0.5As(001), and AlAs(001) investigated with ASP, PES, LEED, and RHEED

    NASA Astrophysics Data System (ADS)

    Bernstein, R. W.; Borg, A.; Husby, H.; Fimland, B.-O.; Grepstad, J. K.

    Arsenic capping and regeneration of MBE-grown GaAs(001), Al 0.5Ga 0.5As(001), and AlAs(001) epilayer surfaces were examined with Auger sputter profiling (ASP), synchrotron radiation and X-ray photoelectron spectroscopy (PES), LEED, and RHEED. It is found that clean, ordered surfaces of different As/Ga(Al) compositions and different surface reconstructions can be prepared in a controlled manner after long-term storage in air, by thermal desorption of the As cap at appropriate annealing temperatures. A protective film of amorphous arsenic was deposited in situ with both As 2 and As 4 molecular beams onto cold substrates. The recorded Auger depth profiles unveil capping layer thicknesses from 0.3 to 3 μm, the thicker for depositions using the As 2 dimer source. The As 3+ surface oxide, formed immediately upon exposure of the passivated wafers to air, remains on the order of 10Åthick, even after storage in atmosphere for several months. Core level photoemission shows selective desorption of this oxide upon annealing in UHV at 250°C. Further heating at 350°C evaporates the protective arsenic cap, and clean, As-terminated Al xGa 1- xAs(001) surfaces with a regular arrayof chemisorbed excess As sbnd As dimers prevail. The recorded LEED and RHEED patterns show a c(4 × 4) surface reconstruction for GaAs(001) and Al 0.5Ga 0.5As(001), whereas this structural phase was observed with RHEED only for the highly reactive AlAs(001) surface. Subsequently annealing in UHV at 450°C causes desorption of the chemisorbed surface arsenic and a concurrent transition from c(4 × 4) to the (2 × 4)/c(2 × 8) surface of As stabilized MBE-grown Al xGa 1- xAs(001). With AlAs(001), surface Al oxidation was observed immediately after annealing at 450°C, in spite of carefully controlled UHV environments

  18. Defects and stresses in MBE-grown GaN and Al{sub 0.3}Ga{sub 0.7}N layers doped by silicon using silane

    SciTech Connect

    Ratnikov, V. V. Kyutt, R. N.; Smirnov, A. N.; Davydov, V. Yu.; Shcheglov, M. P.; Malin, T. V.; Zhuravlev, K. S.

    2013-12-15

    The electric and structural characteristics of silicon-doped GaN and Al{sub 0.3}Ga{sub 0.7}N layers grown by molecular beam epitaxy (MBE) using silane have been analyzed by the Hall effect, Raman spectroscopy, and high-resolution X-ray diffractometry. It is established that the electron concentration linearly increases up to n = 4 × 10{sup 20} cm{sup −3} with an increase in the silane flow rate for GaN:Si, whereas the corresponding dependence for Al{sub 0.3}Ga{sub 0.7}N:Si is sublinear and the maximum electron concentration is found to be n = 4 × 10{sup 19} cm{sup −3}. X-ray measurements of sample macrobending indicate a decrease in biaxial compressive stress with an increase in the electron concentration in both GaN:Si and Al{sub 0.3}Ga{sub 0.7}N:Si layers. The parameters of the dislocation structure, estimated from the measured broadenings of X-ray reflections, are analyzed.

  19. Arsenic incorporation in molecular beam epitaxy (MBE) grown (AlGaIn)(AsSb) layers for 2.0-2.5 μm laser structures on GaSb substrates

    NASA Astrophysics Data System (ADS)

    Simanowski, S.; Walther, M.; Schmitz, J.; Kiefer, R.; Herres, N.; Fuchs, F.; Maier, M.; Mermelstein, C.; Wagner, J.; Weimann, G.

    1999-05-01

    The incorporation of As and In during MBE growth in (AlGaIn)/(AsSb) layers used for the fabrication of diode lasers in the 2.0-2.5 μm wavelength range has been investigated. The As content was found to depend linearly on the beam equivalent pressure for As mole fractions between y=0.05 and y=0.20. Broad area AlGaAsSb/GaInAsSb single-quantum well laser diodes with quasi-cw output at room temperature at an emission wavelength of 2.03 μm and a threshold current density of 515 A/cm 2 for 1370 μm long and 70 μm wide devices have been fabricated. In order to shift the emission wavelength of the laser structures to longer wavelengths, the growth of lattice matched AlGaAsSb/GaInAsSb laser core structures with different In and As mole fractions in the quantum wells has been investigated.

  20. Energy.

    ERIC Educational Resources Information Center

    Shanebrook, J. Richard

    This document describes a course designed to acquaint students with the many societal and technological problems facing the United States and the world due to the increasing demand for energy. The course begins with a writing assignment that involves readings on the environmental philosophy of Native Americans and the Chernobyl catastrophe.…

  1. An aberration-corrected STEM study of structural defects in epitaxial GaN thin films grown by ion beam assisted MBE.

    PubMed

    Poppitz, David; Lotnyk, Andriy; Gerlach, Jürgen W; Lenzner, Jörg; Grundmann, Marius; Rauschenbach, Bernd

    2015-06-01

    Ion-beam assisted molecular-beam epitaxy was used for direct growth of epitaxial GaN thin films on super-polished 6H-SiC(0001) substrates. The GaN films with different film thicknesses were studied using reflection high energy electron diffraction, X-ray diffraction, cathodoluminescence and primarily aberration-corrected scanning transmission electron microscopy techniques. Special attention was devoted to the microstructural characterization of GaN thin films and the GaN-SiC interface on the atomic scale. The results show a variety of defect types in the GaN thin films and at the GaN-SiC interface. A high crystalline quality of the produced hexagonal GaN thin films was demonstrated. The gained results are discussed.

  2. Composition and optical properties of dilute-Sb GaN1-xSbx highly mismatched alloys grown by MBE

    NASA Astrophysics Data System (ADS)

    Shaw, M.; Yu, K. M.; Ting, M.; Powell, R. E. L.; Sarney, W. L.; Svensson, S. P.; Kent, A. J.; Walukiewicz, W.; Foxon, C. T.; Novikov, S. V.; Martin, R. W.

    2014-11-01

    In this work the compositional and optical characterization of three series of dilute-Sb GaN1 - xSbx alloys grown with various Sb flux, under N and Ga-rich conditions, are presented. Using wavelength dispersive x-ray microanalysis and Rutherford backscattering spectroscopy it is found that the N-rich samples (Ga flux < 2.3 × 10-7 Torr) incorporate a higher magnitude of GaSb than the Ga-rich samples (Ga flux > 2.3 × 10-7 Torr) under the same growth conditions. The optical properties of the Ga-rich samples are measured using room temperature cathodoluminescence (CL), photoluminescence (PL) and absorption measurements. A broad luminescence peak is observed around 2.2 eV. The nature and properties of this peak are considered, as is the suitability of these dilute-Sb alloys for use in solar energy conversion devices.

  3. Microscopic structure of GaSb(001) c(2{times}6) surfaces prepared by Sb decapping of MBE-grown samples

    SciTech Connect

    Resch-Esser, U.; Esser, N.; Brar, B.; Kroemer, H.

    1997-06-01

    In this study we report on the microscopic structure of GaSb(001) c(2{times}6) surfaces prepared by Sb decapping. Molecular beam epitaxy grown GaSb(001) layers capped with a protective Sb layer were transferred through the atmosphere into an UHV-analysis system and investigated by scanning tunneling microscopy (STM) and low energy electron diffraction (LEED). After thermal desorption of the capping layer clear c(2{times}6) LEED patterns were observed. STM images show flat surface areas with a rowlike, somewhat disordered structure. High-resolution images resolve individual Sb dimers on the surface. The surface is covered by an incomplete layer of dimerized Sb, adsorbed on a complete second layer of Sb, which is also dimerized in that regions not covered by the fractional Sb top layer. {copyright} {ital 1997} {ital The American Physical Society}

  4. Compositions and chemical bonding in ceramics by quantitative electron energy-loss spectrometry

    SciTech Connect

    Bentley, J.; Horton, L.L.; McHargue, C.J.; McKernan, S.; Carter, C.B.; Revcolevschi, A.; Tanaka, S.; Davis, R.F.

    1993-12-31

    Quantitative electron energy-loss spectrometry was applied to a range of ceramic materials at a spatial resolution of <5 nm. Analysis of Fe L{sub 23} white lines indicated a low-spin state with a charge transfer of {approximately}1.5 electrons/atom onto the Fe atoms implanted into (amorphized) silicon carbide. Gradients of 2 to 5% in the Co:O stoichiometry were measured across 100-nm-thick Co{sub 3}O{sub 4} layers in an oxidized directionally solidified CoO-ZrO{sub 2} eutectic, with the highest O levels near the ZrO{sub 2}. The energy-loss near-edge structures were dramatically different for the two cobalt oxides; those for CO{sub 3}O{sub 4} have been incorrectly ascribed to CoO in the published literature. Kinetically stabilized solid solubility occurred in an AlN-SiC film grown by low-temperature molecular beam epitaxy (MBE) on {alpha}(6H)-SiC, and no detectable interdiffusion occurred in couples of MBE-grown AlN on SiC following annealing at up to 1750C. In diffusion couples of polycrystalline AlN on SiC, interfacial 8H sialon (aluminum oxy-nitride) and pockets of Si{sub 3}N{sub 4}-rich {beta}{prime} sialon in the SiC were detected.

  5. Elongated Quantum Dots of Ge on Si Growth Kinetics Modeling with Respect to the Additional Energy of Edges

    NASA Astrophysics Data System (ADS)

    Lozovoy, K. A.; Pishchagin, A. A.; Kokhanenko, A. P.; Voitsekhovskii, A. V.

    2016-08-01

    In this paper refining of mathematical model for calculation of parameters of selforganised quantum dots (QDs) of Ge on Si grown by the method of molecular beam epitaxy (MBE) is done. Calculations of pyramidal and wedge-like clusters formation energy were conducted with respect to contributions of surface energy, additional edge energy, elastic strain relaxation, and decrease in the atoms attraction to substrate. With the help of well-known model based on the generalization of classical nucleation theory it was shown that elongated islands emerge later than pyramidal clusters. Calculations of QDs surface density and size distribution function for wedge-like clusters with different length to width ratio were performed. The absence of special geometry of islands for which surface density and average size of islands reach points of extremum that was predicted earlier by the model not taking into account energy of edges was revealed when considering the additional contribution of edge formation energy.

  6. Distinguishing cubic and hexagonal phases within InGaN/GaN microstructures using electron energy loss spectroscopy.

    PubMed

    Griffiths, I J; Cherns, D; Albert, S; Bengoechea-Encabo, A; Angel Sanchez, M; Calleja, E; Schimpke, T; Strassburg, M

    2016-05-01

    3D InGaN/GaN microstructures grown by metal organic vapor phase epitaxy (MOVPE) and molecular beam epitaxy (MBE) have been extensively studied using a range of electron microscopy techniques. The growth of material by MBE has led to the growth of cubic GaN material. The changes in these crystal phases has been investigated by Electron Energy Loss Spectroscopy, where the variations in the fine structure of the N K-edge shows a clear difference allowing the mapping of the phases to take place. GaN layers grown for light emitting devices sometimes have cubic inclusions in the normally hexagonal wurtzite structures, which can influence the device electronic properties. Differences in the fine structure of the N K-edge between cubic and hexagonal material in electron energy loss spectra are used to map cubic and hexagonal regions in a GaN/InGaN microcolumnar device. The method of mapping is explained, and the factors limiting spatial resolution are discussed.

  7. Distinguishing cubic and hexagonal phases within InGaN/GaN microstructures using electron energy loss spectroscopy

    PubMed Central

    CHERNS, D; ALBERT, S.; BENGOECHEA‐ENCABO, A.; ANGEL SANCHEZ, M.; CALLEJA, E.; SCHIMPKE, T.; STRASSBURG, M.

    2015-01-01

    Summary 3D InGaN/GaN microstructures grown by metal organic vapor phase epitaxy (MOVPE) and molecular beam epitaxy (MBE) have been extensively studied using a range of electron microscopy techniques. The growth of material by MBE has led to the growth of cubic GaN material. The changes in these crystal phases has been investigated by Electron Energy Loss Spectroscopy, where the variations in the fine structure of the N K‐edge shows a clear difference allowing the mapping of the phases to take place. GaN layers grown for light emitting devices sometimes have cubic inclusions in the normally hexagonal wurtzite structures, which can influence the device electronic properties. Differences in the fine structure of the N K‐edge between cubic and hexagonal material in electron energy loss spectra are used to map cubic and hexagonal regions in a GaN/InGaN microcolumnar device. The method of mapping is explained, and the factors limiting spatial resolution are discussed. PMID:26366483

  8. Energy Performance Assessment of Radiant Cooling System through Modeling and Calibration at Component Level

    SciTech Connect

    Khan, Yasin; Mathur, Jyotirmay; Bhandari, Mahabir S

    2016-01-01

    The paper describes a case study of an information technology office building with a radiant cooling system and a conventional variable air volume (VAV) system installed side by side so that performancecan be compared. First, a 3D model of the building involving architecture, occupancy, and HVAC operation was developed in EnergyPlus, a simulation tool. Second, a different calibration methodology was applied to develop the base case for assessing the energy saving potential. This paper details the calibration of the whole building energy model to the component level, including lighting, equipment, and HVAC components such as chillers, pumps, cooling towers, fans, etc. Also a new methodology for the systematic selection of influence parameter has been developed for the calibration of a simulated model which requires large time for the execution. The error at the whole building level [measured in mean bias error (MBE)] is 0.2%, and the coefficient of variation of root mean square error (CvRMSE) is 3.2%. The total errors in HVAC at the hourly are MBE = 8.7% and CvRMSE = 23.9%, which meet the criteria of ASHRAE 14 (2002) for hourly calibration. Different suggestions have been pointed out to generalize the energy saving of radiant cooling system through the existing building system. So a base case model was developed by using the calibrated model for quantifying the energy saving potential of the radiant cooling system. It was found that a base case radiant cooling system integrated with DOAS can save 28% energy compared with the conventional VAV system.

  9. Investigations on the MBE (molecular beam epitaxy) growth and properties of Al/sub y/Ga/sub y/In/sub 1-x-y/As/InP and InGaAs-InAlAs superlattices: Progress report for the period May 15, 1986-January 31, 1987

    SciTech Connect

    Bhattacharya, P.K.; Gibala, R.

    1987-01-01

    Focus of the work has been to grow wide-bandgap ternary and quaternary semiconductors InAlAs and InGaAlAs by molecular beam epitaxy and to investigate their electronic, optical and structural characteristics. The techniques being used are x-ray, TEM, photoluminescence and absorption, DLTS, Hall transport, impact ionization and pulsed velocity field measurements. The experiments have included both lattice matched and strained layers. It is apparent that the lattice match In/sub 0.52/Al/sub 0.48/As/InP alloys are clustered and dominant D-X trap centers are present in the strained compositions. We are investigating a novel MBE growth technique of growing these alloys directly on GaAs (with a 1 to 4% lattice mismatch) without propagating dislocations. These heteroepitaxial layers and interfaces are being studied by TEM.

  10. Comparison of Four Different Energy Balance Models for Estimating Evapotranspiration in the Midwest United States

    NASA Astrophysics Data System (ADS)

    Singh, R. K.; Senay, G. B.; Verdin, J. P.

    2015-12-01

    Availability of no-cost satellite images helped in development and utilization of remotely sensed images for water use estimation. Remotely sensed images are increasingly used for estimating evapotranspiration (ET) at different temporal and spatial scales. However, selecting any particular model from a plethora of energy balance models for estimating ET is challenging as each different model has its strengths and limitations. We compared four commonly used ET models, namely, Mapping EvapoTranspiration at high Resolution with Internalized Calibration (METRIC) model, Surface Energy Balance Algorithm for Land (SEBAL) model, Surface Energy Balance System (SEBS) model, and Operational Simplified Surface Energy Balance (SSEBop) model using Landsat images for estimating ET in the Midwest United States. We validated our model results using three AmeriFlux cropland sites at Mead, Nebraska. Our results showed that the METRIC and the SSEBop model worked very well at these sites with a root mean square error (RMSE) of less than 1 mm/day and an R2 of 0.96 (N=24). The mean bias error (MBE) was less than 10% for both the METRIC and the SSEBop models. In contrast, the SEBAL and the SEBS models have relatively higher RMSE (> 1.7 mm/day) and MBE (> 27%). However, all four models captured the spatial and temporal variation of ET reasonably well (R2 > 0.80). We found that the model simplification of the SSEBop for operational capability was not at the expense of model accuracy. Since the SSEBop model is relatively less data intensive and independent of user/automatic selection of anchor (hot/dry and cold/wet) pixels, it is more user friendly and operationally efficient. The SSEBop model can be reliably used for estimating water use using Landsat and MODIS images at daily, weekly, monthly, or annual time scale even in data scarce regions for sustainable use of limited water resources.

  11. Heavy Ion Fusion Accelerator Research (HIFAR) half-year report, October 1, 1989--March 31, 1990

    SciTech Connect

    Not Available

    1990-03-01

    This report discusses the following topics: Transverse Emittance Studies on MBE-4; MBE-4 Simulations; Beam Centroid Motion and Misalignments in MBE-4; Survey and Alignment of MBE-4; Energy Analysis of the 5mA MBE-4 Beam; An Improved 10 mA Ion Source for MBE-4; Emittance Degradation via a Wire Grid; Ion Source Development; 2 MV Injector; Electrostatic Quadrupole Prototype Development Activity; Magnetic Induction Core Studies; A Preliminary Consideration of Beam Splitting in Momentum Space; and Status of the Optimization Code HILDA.

  12. Azimuthal reflection high-energy electron diffraction study of MnAs growth on GaAs(001) by molecular beam epitaxy

    SciTech Connect

    Satapathy, Dillip K.; Jenichen, Bernd; Ploog, Klaus H.; Braun, Wolfgang

    2011-07-15

    Azimuthal reflection high-energy electron diffraction (ARHEED) and in situ grazing incidence synchrotron x-ray diffraction techniques are employed to investigate the growth, epitaxial orientation, and interfacial structure of MnAs layers grown on GaAs(001) by molecular beam epitaxy (MBE). We demonstrate the power and reliability of ARHEED scans as a routine tool in characterizing the formation of epitaxial films. The ARHEED scans clearly reveal the formation of the rectangular MnAs unit cell during growth on GaAs(001) for a MnAs layer thickness of 2.1 {+-} 0.2 monolayers with a tensile strain along the MnAs[1120] direction. A periodic coincidence site lattice, which is known to form along the MnAs [0001] direction to release the strain due to the huge lattice mismatch ({approx}30%) also produces periodic satellites of the diffraction spots in the ARHEED scan. The formation of different epitaxial orientations of MnAs during MBE growth can be directly observed using ARHEED scans. ARHEED is demonstrated to have a resolution similar to synchrotron x-ray diffraction with a double crystal monochromator, yielding full width at half maximum values of reflections as small as 0.005 reciprocal lattice units.

  13. Nanoscale Thin Film Electrolytes for Clean Energy Applications

    SciTech Connect

    Nandasiri, Manjula I.; Sanghavi, Rahul P.; Kuchibhatla, Satyanarayana V N T; Thevuthasan, Suntharampillai

    2012-02-01

    Ceria and zirconia based systems can be used as electrolytes to develop solid oxide fuel cells for clean energy production and to prevent air pollution by developing efficient, reliable oxygen sensors. In this study, we have used oxygen plasma assisted molecular beam epitaxy (OPA-MBE) to grow samaria doped ceria (SDC), to understand the role of dopant concentration and geometry of the films towards the ionic conduction in these thin films. We have also discussed the Gd doped CeO2 (GDC) and Gd stabilized ZrO2 (GSZ) multi-layer thin films to investigate the effect of interfacial phenomena on the ionic conductivity of these hetero-structures. We found the optimum concentration to be 15 mol % SmO1.5, for achieving lowest electrical resistance in SDC thin films. The electrical resistance decreases with the increase in film thickness up to 200 nm. The results demonstrate the usefulness of this study towards establishing an optimum dopant concentration and choosing an appropriate thin film thickness to ameliorate the conductance of the SDC material system. Furthermore, we have explored the conductivity of highly oriented GDC and GSZ multi-layer thin films, wherein the conductivity increased with an increase in the number of layers. The extended defects and lattice strain near the interfaces increase the density of oxygen vacancies, which leads to enhanced ionic conductivity in multi-layer thin films.

  14. MBE growth of GaP on a Si substrate

    SciTech Connect

    Sobolev, M. S. Lazarenko, A. A.; Nikitina, E. V.; Pirogov, E. V.; Gudovskikh, A. S.; Egorov, A. Yu.

    2015-04-15

    It is shown that single-crystal GaP buffer layers can be formed on a Si substrate by molecular-beam epitaxy, with the “migration-enhanced epitaxy” procedure applied in the stage in which the nucleating layer is formed. When a GaP layer is produced on a p-type silicon substrate, a p-n junction is created in a natural way between the p-Si substrate and the surface n-Si layer produced by the diffusion of phosphorus into the substrate during the course of the epitaxial growth of GaP. This p-n junction can be used as the first junction of a silicon-based multijunction photovoltaic converter.

  15. MBE Growth of GaAs Whiskers on Si Nanowires

    SciTech Connect

    Maxwell Andrews, Aaron

    2010-01-04

    We present the growth of GaAs nanowhiskers by molecular beam epitaxy on Si (111) nanowires grown by low-pressure chemical vapor deposition. The whiskers grow in the wurtzite phase, along the [0001] direction, on the {l_brace}112{r_brace} facets of the Si nanowire, forming a star-like six-fold radial symmetry. The photoluminescence shows a 30 meV blue shift with respect to bulk GaAs, additionally a GaAs/AlAs core-shell heterostructure shows increased luminescence.

  16. MBE Growth of Graded Structures for Polarized Electron Emitters

    SciTech Connect

    Not Available

    2010-08-25

    SVT Associates, in collaboration with SLAC, have investigated two novel photocathode design concepts in an effort to increase polarization and quantum efficiency. AlGaAsSb/GaAs superlattice photocathodes were fabricated to explore the effect of antimony on device operation. In the second approach, an internal electrical field was created within the superlattice active layer by varying the aluminum composition in AlGaAs/GaAs. A 25% increase in quantum efficiency as a result of the gradient was observed.

  17. MBE Growth of Graded Structures for Polarized Electron Emitters

    SciTech Connect

    Moy, Aaron; Maruyama, T.; Zhou, F.; Brachmann, A.

    2009-08-04

    SVT Associates, in collaboration with SLAC, has investigated two novel photocathode design concepts in an effort to increase polarization and quantum efficiency. AlGaAsSb/GaAs superlattice photocathodes were fabricated to explore the effect of antimony on device operation. In the second approach, an internal electrical field was created within the superlattice active layer by varying the aluminum composition in AlGaAs/GaAs. A 25% increase in quantum efficiency as a result of the gradient was observed.

  18. Getting the Right Answers for the Right Reasons: Toward Predictive Molecular Simulations of Water with Many-Body Potential Energy Functions.

    PubMed

    Paesani, Francesco

    2016-09-20

    The central role played by water in fundamental processes relevant to different disciplines, including chemistry, physics, biology, materials science, geology, and climate research, cannot be overemphasized. It is thus not surprising that, since the pioneering work by Stillinger and Rahman, many theoretical and computational studies have attempted to develop a microscopic description of the unique properties of water under different thermodynamic conditions. Consequently, numerous molecular models based on either molecular mechanics or ab initio approaches have been proposed over the years. However, despite continued progress, the correct prediction of the properties of water from small gas-phase clusters to the liquid phase and ice through a single molecular model remains challenging. To large extent, this is due to the difficulties encountered in the accurate modeling of the underlying hydrogen-bond network in which both number and strength of the hydrogen bonds vary continuously as a result of a subtle interplay between energetic, entropic, and nuclear quantum effects. In the past decade, the development of efficient algorithms for correlated electronic structure calculations of small molecular complexes, accompanied by tremendous progress in the analytical representation of multidimensional potential energy surfaces, opened the doors to the design of highly accurate potential energy functions built upon rigorous representations of the many-body expansion (MBE) of the interaction energies. This Account provides a critical overview of the performance of the MB-pol many-body potential energy function through a systematic analysis of energetic, structural, thermodynamic, and dynamical properties as well as of vibrational spectra of water from the gas to the condensed phase. It is shown that MB-pol achieves unprecedented accuracy across all phases of water through a quantitative description of each individual term of the MBE, with a physically correct representation

  19. Getting the Right Answers for the Right Reasons: Toward Predictive Molecular Simulations of Water with Many-Body Potential Energy Functions.

    PubMed

    Paesani, Francesco

    2016-09-20

    The central role played by water in fundamental processes relevant to different disciplines, including chemistry, physics, biology, materials science, geology, and climate research, cannot be overemphasized. It is thus not surprising that, since the pioneering work by Stillinger and Rahman, many theoretical and computational studies have attempted to develop a microscopic description of the unique properties of water under different thermodynamic conditions. Consequently, numerous molecular models based on either molecular mechanics or ab initio approaches have been proposed over the years. However, despite continued progress, the correct prediction of the properties of water from small gas-phase clusters to the liquid phase and ice through a single molecular model remains challenging. To large extent, this is due to the difficulties encountered in the accurate modeling of the underlying hydrogen-bond network in which both number and strength of the hydrogen bonds vary continuously as a result of a subtle interplay between energetic, entropic, and nuclear quantum effects. In the past decade, the development of efficient algorithms for correlated electronic structure calculations of small molecular complexes, accompanied by tremendous progress in the analytical representation of multidimensional potential energy surfaces, opened the doors to the design of highly accurate potential energy functions built upon rigorous representations of the many-body expansion (MBE) of the interaction energies. This Account provides a critical overview of the performance of the MB-pol many-body potential energy function through a systematic analysis of energetic, structural, thermodynamic, and dynamical properties as well as of vibrational spectra of water from the gas to the condensed phase. It is shown that MB-pol achieves unprecedented accuracy across all phases of water through a quantitative description of each individual term of the MBE, with a physically correct representation

  20. Feasibility study to develop a marketing plan and strategy for increasing the participation of minority business enterprises and black colleges and universities in energy-related industries

    SciTech Connect

    Not Available

    1983-01-31

    This study was designed to identify and test an alternative method for more effective means of involving Minority Business Enterprises (MBEs) and historically Black colleges and universities (HBCUs) in energy-related business opportunities. Based upon the analysis of MBE and HBCU technical assistance programs, DOD's, DOE's, and TVA's procurement processes and the results of the test used to validate the adaptability of a performance tested alternative marketing system to energy-related industries. Based on the findings and conclusions of this study and in order to meet the objectives of: (1) increasing participation of MBEs and HBCUs in TVA and energy-related industries; (2) ensuring that the statutory objectives of Title VI of the Civil Rights Act of 1964 and Public Law 95-507 are achieved in the public and private energy market sectors; and (3) meeting President Reagan's goal of realizing $22 billion in minority contracts within the next three years, BTW recommends that the Portfolio System be adapted, demonstrated, installed and deployed in large-scale, complex, energy-related research and development facilities and power utilities' procurement programs.

  1. The interaction of C60 on Si(111) 7x7 studied by Supersonic Molecular Beams: interplay between precursor kinetic energy and substrate temperature in surface activated processes.

    NASA Astrophysics Data System (ADS)

    Aversa, Lucrezia; Taioli, Simone; Nardi, Marco; Tatti, Roberta; Verucchi, Roberto; Iannotta, Salvatore

    2015-06-01

    Buckminsterfullerene (C60) is a molecule fully formed of carbon that can be used, owing to its electronic and mechanical properties, as “clean” precursor for the growth of carbon-based materials, ranging from ?-conjugated systems (graphenes) to synthesized species, e.g. carbides such as silicon carbide (SiC). To this goal, C60 cage rupture is the main physical process that triggers material growth. Cage breaking can be obtained either thermally by heating up the substrate to high temperatures (630°C), after C60 physisorption, or kinetically by using Supersonic Molecular Beam Epitaxy (SuMBE) techniques. In this work, aiming at demonstrating the growth of SiC thin films by C60 supersonic beams, we present the experimental investigation of C60 impacts on Si(111) 7x7 kept at 500°C for translational kinetic energies ranging from 18 to 30 eV. The attained kinetically activated synthesis of SiC submonolayer films is probed by in-situ surface electron spectroscopies (XPS and UPS). Furthermore, in these experimental conditions the C60-Si(111) 7×7 collision has been studied by computer simulations based on a tight-binding approximation to Density Functional Theory, DFT. Our theoretical and experimental findings point towards a kinetically driven growth of SiC on Si, where C60 precursor kinetic energy plays a crucial role, while temperature is relevant only after cage rupture to enhance Si and carbon reactivity. In particular, we observe a counterintuitive effect in which for low kinetic energy (below 22 eV), C60 bounces back without breaking more effectively at high temperature due to energy transfer from excited phonons. At higher kinetic energy (22 < K < 30 eV), for which cage rupture occurs, temperature enhances reactivity without playing a major role in the cage break. These results are in good agreement with ab-initio molecular dynamics simulations. SuMBE is thus a technique able to drive materials growth at low temperature regime.

  2. Strain relaxation of CdTe on Ge studied by medium energy ion scattering

    NASA Astrophysics Data System (ADS)

    Pillet, J. C.; Pierre, F.; Jalabert, D.

    2016-10-01

    We have used the medium energy ion scattering (MEIS) technique to assess the strain relaxation in molecular-beam epitaxial (MBE) grown CdTe (2 1 1)/Ge (2 1 1) system. A previous X-ray diffraction study, on 10 samples of the same heterostructure having thicknesses ranging from 25 nm to 10 μm has allowed the measurement of the strain relaxation on a large scale. However, the X-ray diffraction measurements cannot achieve a stress measurement in close proximity to the CdTe/Ge interface at the nanometer scale. Due to the huge lattice misfit between the CdTe and Ge, a high degree of disorder is expected at the interface. The MEIS in channeling mode is a good alternative in order to profile defects with a high depth resolution. For a 21 nm thick CdTe layer, we observed, at the interface, a high density of Cd and/or Te atoms moved from their expected crystallographic positions followed by a rapid recombination of defects. Strain relaxation mechanisms in the vicinity of the interface are discussed

  3. Feasibility study to develop a marketing plan and strategy for increasing the participation of minority business enterprises and black colleges and universities in energy-related industries. Final report

    SciTech Connect

    Not Available

    1983-01-31

    This study was designed to identify and test an alternative method for more effective means of involving Minority Business Enterprises (MBEs) and historically Black colleges and universities (HBUs) in energy-related business opportunities. Based upon the analysis of MBE and HBCU technical assistance programs, DOD's DOE's, and TVA's procurement processes and the results of the test used to validate the adaptability of a performance tested alternative marketing system to energy-related industries. Based on the findings and conclusions of this study and in order to meet the objectives of: (1) increasing participation of MBEs and HBCUs in TVA and energy-related industries; (2) ensuring that the statutory objectives of Title VI of the Civil Rights Act of 1964 and Public Law 95-507 are achieved in the public and private energy market sectors; and (3) meeting President Reagan's goal of realizing $22 billion in minority contracts within the next three years, BTW recommends that the Portfolio System be adapted, demonstrated, installed and deployed in large-scale, complex, energy-related research and development facilities and power utilities' procurement programs.

  4. Energy 101: Geothermal Energy

    SciTech Connect

    2014-05-27

    See how we can generate clean, renewable energy from hot water sources deep beneath the Earth's surface. The video highlights the basic principles at work in geothermal energy production, and illustrates three different ways the Earth's heat can be converted into electricity.

  5. Energy 101: Geothermal Energy

    ScienceCinema

    None

    2016-07-12

    See how we can generate clean, renewable energy from hot water sources deep beneath the Earth's surface. The video highlights the basic principles at work in geothermal energy production, and illustrates three different ways the Earth's heat can be converted into electricity.

  6. Heavy Ion Fusion Accelerator Research (HIFAR) year-end report, April 1, 1986-September 30, 1986

    SciTech Connect

    Not Available

    1986-10-01

    Activities are reported on MBE-4, the four-beam proof-of-principle ion induction linear accelerator with the capability of beam-current amplification. Mechanical aspects of MBE-4, quadrupole insulator performance, and pulsers are discussed. The computer code, SLID, has been used to help understand the longitudinal beam dynamics in MBE-4. A computer-controlled emittance scanning system is in use in MBE-4. A systematic effort is under way to discover and correct all the defects peculiar to the low energy part of the linac design code. (LEW)

  7. Rotational Energy.

    ERIC Educational Resources Information Center

    Lockett, Keith

    1988-01-01

    Demonstrates several objects rolling down a slope to explain the energy transition among potential energy, translational kinetic energy, and rotational kinetic energy. Contains a problem from Galileo's rolling ball experiment. (YP)

  8. Energy: Conservation, Energy Briefs

    ERIC Educational Resources Information Center

    Nation's Schools and Colleges, 1975

    1975-01-01

    A comprehensive energy conservation program at College of the Holy Cross has saved nearly one-third of the fuel oil and one-fifth of the electricity used at the college; briefs on boilers, lights, design. (Author/MLF)

  9. Energy Technology.

    ERIC Educational Resources Information Center

    Eaton, William W.

    Reviewed are technological problems faced in energy production including locating, recovering, developing, storing, and distributing energy in clean, convenient, economical, and environmentally satisfactory manners. The energy resources of coal, oil, natural gas, hydroelectric power, nuclear energy, solar energy, geothermal energy, winds, tides,…

  10. Energy policy: energy prospects

    SciTech Connect

    Marcus, G.H.

    1983-08-18

    The Reagan administration, after reversing the trend of the 1970s toward government participation in energy programs, will continue its non-intervention philosophy in the National Energy Policy Plan (NEP III) update now under development. The plan eliminates oil and gas price controls, reduces or eliminates commercialization and tax-incentive programs for solar energy and synthetic fuels, and reduces research and development programs for near-term technologies. Large-scale, high-risk energy research will receive federal support if there is a potential commercial future. A level of regulation will remain, at least until alternative power systems sufficiently alter the non-competitive nature of utilities. Issues being raised are whether or not industry can provide needed service under deregulation, whether states will be able to set their own standards, whether the federal government should support new or necessary industries, whether private industry can compete against foreign government-backed firms, and the long-term consequences for energy development of widely fluctuating federal policies. (DCK)

  11. Renewable energy.

    PubMed

    Destouni, Georgia; Frank, Harry

    2010-01-01

    The Energy Committee of the Royal Swedish Academy of Sciences has in a series of projects gathered information and knowledge on renewable energy from various sources, both within and outside the academic world. In this article, we synthesize and summarize some of the main points on renewable energy from the various Energy Committee projects and the Committee's Energy 2050 symposium, regarding energy from water and wind, bioenergy, and solar energy. We further summarize the Energy Committee's scenario estimates of future renewable energy contributions to the global energy system, and other presentations given at the Energy 2050 symposium. In general, international coordination and investment in energy research and development is crucial to enable future reliance on renewable energy sources with minimal fossil fuel use.

  12. Solar Energy.

    ERIC Educational Resources Information Center

    Eaton, William W.

    Presented is the utilization of solar radiation as an energy resource principally for the production of electricity. Included are discussions of solar thermal conversion, photovoltic conversion, wind energy, and energy from ocean temperature differences. Future solar energy plans, the role of solar energy in plant and fossil fuel production, and…

  13. Gravitational energy

    NASA Astrophysics Data System (ADS)

    Katz, Joseph

    2005-12-01

    Observers at rest in a stationary spacetime flat at infinity can measure small amounts of rest-mass + internal energies + kinetic energies + pressure energy in a small volume of fluid attached to a local inertial frame. The sum of these small amounts is the total 'matter energy', EM, for those observers. If Mc2 is the total mass energy, the difference Mc2 - EM is the binding gravitational energy. Misner, Thorne and Wheeler (MTW) evaluated the gravitational energy of a spherically symmetric static spacetime. Here we show how to calculate gravitational energy in any static and stationary spacetimes with isolated sources with a set of observers at rest. The result of MTW is recovered and we find that electromagnetic and gravitational 3-covariant energy densities in conformastatic spacetimes are of opposite signs. Various examples suggest that gravitational energy is negative in spacetimes with special symmetries or when the energy momentum tensor satisfies usual energy conditions.

  14. Energy overview

    NASA Technical Reports Server (NTRS)

    Slone, H. O.

    1980-01-01

    The experience, capabilities, and facilities being utilized at NASA Lewis in support of energy programs conducted by the Department of Energy and other agencies are discussed. Background information is given regarding NASA's involvement in solving energy problems.

  15. Energy Models

    EPA Science Inventory

    Energy models characterize the energy system, its evolution, and its interactions with the broader economy. The energy system consists of primary resources, including both fossil fuels and renewables; power plants, refineries, and other technologies to process and convert these r...

  16. Energy resources

    NASA Technical Reports Server (NTRS)

    1973-01-01

    A statistical analysis of the availability of fossil fuels for energy and non-energy production is presented. The cumulative requirements for petroleum, natural gas, and coal are discussed. Alternate forms of energy are described and the advantages and limitations are analyzed. Emphasis is placed on solar energy availability and methods for conversion. The Federal energy research and development funding for energy sources is tabulated.

  17. Energy Theater

    NASA Astrophysics Data System (ADS)

    Daane, Abigail R.; Wells, Lindsay; Scherr, Rachel E.

    2014-05-01

    Energy Theater is a dynamic, full-body activity that engages all students in representing the flow of energy in various phenomena, such as a light bulb burning steadily or a refrigerator cooling food. In Energy Theater, each participant acts as a unit of energy that has one form at a time. Regions on the floor correspond to objects in a physical scenario, and participants move from one region to another to demonstrate the flow of energy among objects. (See Figs. 1, 3, and 4.) The goal of Energy Theater is for students to track energy transfers and transformations in real-world energy scenarios while employing the principle of energy conservation and disambiguating matter and energy. Unlike most representations of energy, which are static before-and-after accounting schemes for energy changes, Energy Theater is a dynamic representation that provides a natural stepping stone toward the more advanced ideas of energy density, energy current, and a continuity equation relating them. The fact that conservation of energy is embedded in the representation encourages students to "find the energy" in situations where it may be imperceptible. The rules of Energy Theater are listed in Fig. 2.

  18. Energy Theater

    ERIC Educational Resources Information Center

    Daane, Abigail R.; Wells, Lindsay; Scherr, Rachel E.

    2014-01-01

    Energy Theater is a dynamic, full-body activity that engages all students in representing the flow of energy in various phenomena, such as a light bulb burning steadily or a refrigerator cooling food. In Energy Theater, each participant acts as a unit of energy that has one form at a time. Regions on the floor correspond to objects in a physical…

  19. Geothermal Energy.

    ERIC Educational Resources Information Center

    Nemzer, Marilyn; Page, Deborah

    This curriculum unit describes geothermal energy in the context of the world's energy needs. It addresses renewable and nonrenewable energy sources with an in-depth study of geothermal energy--its geology, its history, and its many uses. Included are integrated activities involving science, as well as math, social studies, and language arts.…

  20. Geothermal Energy.

    ERIC Educational Resources Information Center

    Conservation and Renewable Energy Inquiry and Referral Service (DOE), Silver Spring, MD.

    An introduction to geothermal energy is provided in this discussion of: (1) how a geothermal reservoir works; (2) how to find geothermal energy; (3) where it is located; (4) electric power generation using geothermal energy; (5) use of geothermal energy as a direct source of heat; (6) geopressured reservoirs; (7) environmental effects; (8)…

  1. Energy Day.

    ERIC Educational Resources Information Center

    Thomas, Peter

    1997-01-01

    Describes a program in which students present their displays in the normal science-fair style but without the competitive element and more as a "science-share". Describes an "energy day" celebration which included an energy exhibition and engaged students in an "energy decathlon" that challenged them with tasks encompassing many aspects of energy.…

  2. Save Energy $.

    ERIC Educational Resources Information Center

    Hirsch, Thomas E., III; Shapiro, Robert F.

    1986-01-01

    Large institutional energy users can reduce energy costs by constructing and operating steam and electricity cogeneration facilities and purchasing their own gas at lower prices rather than relying on local distributors. (MSE)

  3. Energy Analysis.

    ERIC Educational Resources Information Center

    Bazjanac, Vladimir

    1981-01-01

    The Aquatic Center at Corvallis (Oregon) is analyzed for energy use. Energy conservation in the building would be accomplished best through heavy insulation of exterior surfaces and the maximization of passive solar gain. (Author/MLF)

  4. Geothermal Energy

    SciTech Connect

    Steele, B.C.; Harman, G.; Pitsenbarger, J.

    1996-02-01

    Geothermal Energy Technology (GET) announces on a bimonthly basis the current worldwide information available on the technologies required for economic recovery of geothermal energy and its use as direct heat or for electric power production.

  5. Geothermal Energy.

    ERIC Educational Resources Information Center

    Reed, Marshall J.

    1979-01-01

    During 1978, exploration for geothermal energy continued at the same moderately low level of the past few years in most countries. The U.S. is the only country where the development of geothermal energy depends on private industry. (BB)

  6. Hydrogen energy.

    PubMed

    Edwards, P P; Kuznetsov, V L; David, W I F

    2007-04-15

    The problem of anthropogenically driven climate change and its inextricable link to our global society's present and future energy needs are arguably the greatest challenge facing our planet. Hydrogen is now widely regarded as one key element of a potential energy solution for the twenty-first century, capable of assisting in issues of environmental emissions, sustainability and energy security. Hydrogen has the potential to provide for energy in transportation, distributed heat and power generation and energy storage systems with little or no impact on the environment, both locally and globally. However, any transition from a carbon-based (fossil fuel) energy system to a hydrogen-based economy involves significant scientific, technological and socio-economic barriers. This brief report aims to outline the basis of the growing worldwide interest in hydrogen energy and examines some of the important issues relating to the future development of hydrogen as an energy vector.

  7. Energy Digest.

    ERIC Educational Resources Information Center

    Gaddy, Carol T., Ed.; Wells, Kathy, Ed.

    This collection of reprints offers practical solutions, not readily available elsewhere, to everyday energy problems, such as high utility bills, insulating windows, getting more gas mileage, or buying a more efficient washer or refrigerator. The Arkansas Energy Office provides a weekly column of energy news and conservation tips to newspapers,…

  8. Geothermal Energy

    SciTech Connect

    Steele, B.C.; Pichiarella, L.S.; Kane, L.S.; Henline, D.M.

    1995-01-01

    Geothermal Energy (GET) announces on a bimonthly basis the current worldwide information available on the technologies required for economic recovery of geothermal energy and its use as direct heat or for electric power production. This publication contains the abstracts of DOE reports, journal articles, conference papers, patents, theses, and monographs added to the Energy Science and Technology Database during the past two months.

  9. Energy Builders.

    ERIC Educational Resources Information Center

    Instructor, 1982

    1982-01-01

    Due to increasing energy demands and decreasing supplies, it is important for teachers to provide students with a solid foundation for energy decision making. Activities are presented which offer hands-on experiences with four sources of energy: wind, water, sun, and fossil fuels. (JN)

  10. Geothermal Energy.

    ERIC Educational Resources Information Center

    Eaton, William W.

    Described are the origin and nature of geothermal energy. Included is the history of its development as an energy source, technological considerations affecting its development as an energy source, its environmental effects, economic considerations, and future prospects of development in this field. Basic system diagrams of the operation of a…

  11. Energy Storage.

    ERIC Educational Resources Information Center

    Eaton, William W.

    Described are technological considerations affecting storage of energy, particularly electrical energy. The background and present status of energy storage by batteries, water storage, compressed air storage, flywheels, magnetic storage, hydrogen storage, and thermal storage are discussed followed by a review of development trends. Included are…

  12. ENERGY-10

    1996-06-30

    ENERGY-10 is a software tool that helps architects, builders, and engineers quickly identify the most cost-effective, energy-saving measures to take in designing a low-energy building. The simulation software is suitable for examining small commercial and residential buildings that are characterized by one, or two thermal zones (generally less than 10,000 ft2.)

  13. Biomass energy

    SciTech Connect

    Smil, V.

    1983-01-01

    This book offers a broad, interdisciplinary approach to assessing the factors that are key determinants to the use of biomass energies, stressing their limitations, complexities, uncertainties, links, and consequences. Considers photosynthesis, energy costs of nutrients, problems with monoculture, and the energy analysis of intensive tree plantations. Subjects are examined in terms of environmental and economic impact. Emphasizes the use and abuse of biomass energies in China, India, and Brazil. Topics include forests, trees for energy, crop residues, fuel crops, aquatic plants, and animal and human wastes. Recommended for environmental engineers and planners, and those involved in ecology, systematics, and forestry.

  14. Marine energy.

    PubMed

    Kerr, David

    2007-04-15

    Marine energy is renewable and carbon free and has the potential to make a significant contribution to energy supplies in the future. In the UK, tidal power barrages and wave energy could make the largest contribution, and tidal stream energy could make a smaller but still a useful contribution. This paper provides an overview of the current status and prospects for electrical generation from marine energy. It concludes that a realistic potential contribution to UK electricity supplies is approximately 80 TWh per year but that many years of development and investment will be required if this potential is to be realized. PMID:17272244

  15. Energy 101: Home Energy Assessment

    SciTech Connect

    2010-01-01

    A home energy checkup helps owners determine where their house is losing energy and money - and how such problems can be corrected to make the home more energy efficient. A professional technician - often called an energy auditor - can give your home a checkup. You can also do some of the steps yourself. Items shown here include checking for leaks, examining insulation, inspecting the furnace and ductwork, performing a blower door test and using an infrared camera.

  16. Energy 101: Home Energy Assessment

    ScienceCinema

    None

    2016-07-12

    A home energy checkup helps owners determine where their house is losing energy and money - and how such problems can be corrected to make the home more energy efficient. A professional technician - often called an energy auditor - can give your home a checkup. You can also do some of the steps yourself. Items shown here include checking for leaks, examining insulation, inspecting the furnace and ductwork, performing a blower door test and using an infrared camera.

  17. Energy Audits. Energy Technology Series.

    ERIC Educational Resources Information Center

    Center for Occupational Research and Development, Inc., Waco, TX.

    This course in energy audits is one of 16 courses in the Energy Technology Series developed for an Energy Conservation-and-Use Technology curriculum. Intended for use in two-year postsecondary technical institutions to prepare technicians for employment, the courses are also useful in industry for updating employees in company-sponsored training…

  18. Energy Drinks

    PubMed Central

    Ugochukwu, Chio; Bagot, Kara; Khalili, David; Zaky, Christine

    2012-01-01

    Objective: The market and degree of consumption of energy drinks have exponentially expanded while studies that assess their psychological effects and impact on quality of life remain in the early stages, albeit on the rise. This review aims to examine the literature for evidence of the psychological effects of energy drinks and their impact on the sense of well-being and quality of life. Methods: Studies were identified through Pubmed, Medline, and PsycINFO searches from the dates of 1990 to 2011, published in English, using the keywords energy or tonic drinks, psychological effects, caffeine and cognitive functions, mood, sleep, quality of life, well-being, and mental illness. Three authors agreed independently on including 41 studies that met specific selection criteria. Results: The literature reveals that people most commonly consume energy drinks to promote wakefulness, to increase energy, and to enhance the experience of alcohol intoxication. A number of studies reveal that individuals who consume energy drinks with alcohol were more inclined to be involved in risk-taking behaviors. There was also excessive daytime sleepiness the day following energy drink consumption. Contrary to expectations, the impact of energy drinks on quality of life and well-being was equivocal. Conclusions: Energy drinks have mixed psychological and well-being effects. There is a need to investigate the different contexts in which energy drinks are consumed and the impact on mental health, especially in the psychiatrically ill. PMID:22347688

  19. Transporation Energy

    SciTech Connect

    Clifford Mirman; Promod Vohra

    2012-06-30

    This Transportation Energy Project is comprised of four unique tasks which work within the railroad industry to provide solutions in various areas of energy conservation. These tasks addressed: energy reducing yard related decision issues; alternate fuels; energy education, and energy storage for railroad applications. The NIU Engineering and Technology research team examined these areas and provided current solutions which can be used to both provide important reduction in energy usage and system efficiency in the given industry. This project also sought a mode in which rural and long-distance education could be provided. The information developed in each of the project tasks can be applied to all of the rail companies to assist in developing efficiencies.

  20. Wind energy.

    PubMed

    Leithead, W E

    2007-04-15

    From its rebirth in the early 1980s, the rate of development of wind energy has been dramatic. Today, other than hydropower, it is the most important of the renewable sources of power. The UK Government and the EU Commission have adopted targets for renewable energy generation of 10 and 12% of consumption, respectively. Much of this, by necessity, must be met by wind energy. The US Department of Energy has set a goal of 6% of electricity supply from wind energy by 2020. For this potential to be fully realized, several aspects, related to public acceptance, and technical issues, related to the expected increase in penetration on the electricity network and the current drive towards larger wind turbines, need to be resolved. Nevertheless, these challenges will be met and wind energy will, very likely, become increasingly important over the next two decades. An overview of the technology is presented.

  1. Energy storage

    NASA Astrophysics Data System (ADS)

    Kaier, U.

    1981-04-01

    Developments in the area of energy storage are characterized, with respect to theory and laboratory, by an emergence of novel concepts and technologies for storing electric energy and heat. However, there are no new commercial devices on the market. New storage batteries as basis for a wider introduction of electric cars, and latent heat storage devices, as an aid for solar technology applications, with satisfactory performance standards are not yet commercially available. Devices for the intermediate storage of electric energy for solar electric-energy systems, and for satisfying peak-load current demands in the case of public utility companies are considered. In spite of many promising novel developments, there is yet no practical alternative to the lead-acid storage battery. Attention is given to central heat storage for systems transporting heat energy, small-scale heat storage installations, and large-scale technical energy-storage systems.

  2. Wind energy.

    PubMed

    Leithead, W E

    2007-04-15

    From its rebirth in the early 1980s, the rate of development of wind energy has been dramatic. Today, other than hydropower, it is the most important of the renewable sources of power. The UK Government and the EU Commission have adopted targets for renewable energy generation of 10 and 12% of consumption, respectively. Much of this, by necessity, must be met by wind energy. The US Department of Energy has set a goal of 6% of electricity supply from wind energy by 2020. For this potential to be fully realized, several aspects, related to public acceptance, and technical issues, related to the expected increase in penetration on the electricity network and the current drive towards larger wind turbines, need to be resolved. Nevertheless, these challenges will be met and wind energy will, very likely, become increasingly important over the next two decades. An overview of the technology is presented. PMID:17272245

  3. Solar energy

    NASA Technical Reports Server (NTRS)

    Rapp, D.

    1981-01-01

    The book opens with a review of the patterns of energy use and resources in the United States, and an exploration of the potential of solar energy to supply some of this energy in the future. This is followed by background material on solar geometry, solar intensities, flat plate collectors, and economics. Detailed attention is then given to a variety of solar units and systems, including domestic hot water systems, space heating systems, solar-assisted heat pumps, intermediate temperature collectors, space heating/cooling systems, concentrating collectors for high temperatures, storage systems, and solar total energy systems. Finally, rights to solar access are discussed.

  4. Nuclear energy.

    PubMed

    Grandin, Karl; Jagers, Peter; Kullander, Sven

    2010-01-01

    Nuclear energy can play a role in carbon free production of electrical energy, thus making it interesting for tomorrow's energy mix. However, several issues have to be addressed. In fission technology, the design of so-called fourth generation reactors show great promise, in particular in addressing materials efficiency and safety issues. If successfully developed, such reactors may have an important and sustainable part in future energy production. Working fusion reactors may be even more materials efficient and environmental friendly, but also need more development and research. The roadmap for development of fourth generation fission and fusion reactors, therefore, asks for attention and research in these fields must be strengthened.

  5. Nuclear energy.

    PubMed

    Grandin, Karl; Jagers, Peter; Kullander, Sven

    2010-01-01

    Nuclear energy can play a role in carbon free production of electrical energy, thus making it interesting for tomorrow's energy mix. However, several issues have to be addressed. In fission technology, the design of so-called fourth generation reactors show great promise, in particular in addressing materials efficiency and safety issues. If successfully developed, such reactors may have an important and sustainable part in future energy production. Working fusion reactors may be even more materials efficient and environmental friendly, but also need more development and research. The roadmap for development of fourth generation fission and fusion reactors, therefore, asks for attention and research in these fields must be strengthened. PMID:20873683

  6. Solar energy

    NASA Astrophysics Data System (ADS)

    Rapp, D.

    The book opens with a review of the patterns of energy use and resources in the United States, and an exploration of the potential of solar energy to supply some of this energy in the future. This is followed by background material on solar geometry, solar intensities, flat plate collectors, and economics. Detailed attention is then given to a variety of solar units and systems, including domestic hot water systems, space heating systems, solar-assisted heat pumps, intermediate temperature collectors, space heating/cooling systems, concentrating collectors for high temperatures, storage systems, and solar total energy systems. Finally, rights to solar access are discussed.

  7. Quantitative analysis of the Ge concentration in a SiGe quantum well: comparison of low-energy RBS and SIMS measurements.

    PubMed

    Krecar, D; Rosner, M; Draxler, M; Bauer, P; Hutter, H

    2006-01-01

    The germanium concentration and the position and thickness of the quantum well in molecular beam epitaxy (MBE)-grown SiGe were quantitatively analyzed via low-energy Rutherford backscattering (RBS) and secondary ion mass spectrometry (SIMS). In these samples, the concentrations of Si and Ge were assumed to be constant, except for the quantum well, where the germanium concentration was lower. The thickness of the analyzed quantum well was about 12 nm and it was situated at a depth of about 60 nm below the surface. A dip showed up in the RBS spectra due to the lower germanium concentration in the quantum well, and this was evaluated. Good depth resolution was required in order to obtain quantitative results, and this was obtained by choosing a primary energy of 500 keV and a tilt angle of 51 degrees with respect to the surface normal. Quantitative information was deduced from the raw data by comparing it with SIMNRA simulated spectra. The SIMS measurements were performed with oxygen primary ions. Given the response function of the SIMS instrument (the SIMS depth profile of the germanium delta (delta) layer), and using the forward convolution (point-to-point convolution) model, it is possible to determine the germanium concentration and the thickness of the analyzed quantum well from the raw SIMS data. The aim of this work was to compare the results obtained via RBS and SIMS and to show their potential for use in the semiconductor and microelectronics industry. The detection of trace elements (here the doping element antimony) that could not be evaluated with RBS in low-energy mode is also demonstrated using SIMS instead.

  8. Energy Conservation.

    ERIC Educational Resources Information Center

    Land, Amy A.

    This selection of class activities involves a sequence of 10 class sessions. The goal of the collection is to aid students in learning the concepts of energy conservation and to put this knowledge into practice. Attention is also given to the development of alternate energy sources. Each lesson includes an activity title, motivational hints,…

  9. Energy Underground.

    ERIC Educational Resources Information Center

    Wiley, Catherina L.

    2003-01-01

    Describes a unit to study the cycling of matter and energy through speleology using cooperative learning groups. Integrates the topic with zoology, biogeochemistry, paleontology, and meteorology. Includes a sample rubric for a salt block cave presentation, unit outline, and processes for studying matter and energy processes in caves. (Author/KHR)

  10. Magma energy

    SciTech Connect

    Dunn, J.C.

    1987-01-01

    The thermal energy contained in magmatic systems represents a huge potential resource. In the US, useful energy contained in molten and partially-molten magma within the upper 10 km of the crust has been estimated at 5 to 50 x 10/sup 22/ J (50,000 to 500,000 Quads). The objective of the Magma Energy Extraction Program is to determine the engineering feasibility of locating, accessing, and utilizing magma as a viable energy resource. This program follows the DOE/OBES-funded Magma Energy Research Project that concluded scientific feasibility of the magma energy concept. A primary long-range goal of this program is to conduct an energy extraction experiment directly in a molten, crustal magma body. Critical to determining engineering feasibility are several key technology tasks: (1) Geophysics - to obtain detailed definition of potential magma targets, (2) Geochemistry/Materials - to characterize the magma environment and select compatible engineering materials, (3) Drilling - to develop drilling and completion techniques for entry into a magma body, and (4) Energy Extraction - to develop heat extraction technology.

  11. Energy Solutions

    ERIC Educational Resources Information Center

    Sobieski, Jeff

    2010-01-01

    Education facilities managers are faced with a daunting set of challenges: They must find new ways to reduce energy consumption and carry out greener energy policies. HVAC typically accounts for more than 30% of a building's electricity costs, so there is a clear incentive to eliminate unnecessary heating and cooling of unoccupied rooms. With more…

  12. Geothermal Energy.

    ERIC Educational Resources Information Center

    Bufe, Charles Glenn

    1983-01-01

    Major activities, programs, and conferences in geothermal energy during 1982 are highlighted. These include first comprehensive national assessment of U.S. low-temperature geothermal resources (conducted by U.S. Geological Survey and Department of Energy), map production by U.S. Geological Survey, geothermal plant production, and others. (JN)

  13. Energy - 1977.

    ERIC Educational Resources Information Center

    Kansas State Board of Regents, Topeka.

    A checklist of energy consumption reduction measures for universities is provided with the intent of achieving rapid and significant energy savings at minimal cost. Measures described should be within the scope of accomplishment by regular university operating and maintenance personnel. The measures involve non-technical actions such as adjusting…

  14. Energy Demands

    ERIC Educational Resources Information Center

    Wilkinson, Ron

    2010-01-01

    When construction slows and campus operating expenses are under the microscope, it is more important than ever to save energy dollars with the equipment and staff on hand. For the facilities manager who thinks out of the box, significant savings can be found on most school and college campuses. This article provides energy-conservation tips that…

  15. Energy Adventure.

    ERIC Educational Resources Information Center

    Oak Ridge Associated Universities, TN.

    Designed as an interdisciplinary, supplemental teaching guide, this document provides fundamental information about energy supply, use, and conservation and related learning activities for secondary students. Eight units address the following topics: energy history, petroleum, natural gas, coal, electricity, alternative sources, energy…

  16. Renewable Energy

    NASA Astrophysics Data System (ADS)

    Boyle, Godfrey

    2004-05-01

    Stimulated by recent technological developments and increasing concern over the sustainability and environmental impact of conventional fuel usage, the prospect of producing clean, sustainable power in substantial quantities from renewable energy sources arouses interest around the world. This book provides a comprehensive overview of the principal types of renewable energy--including solar, thermal, photovoltaics, bioenergy, hydro, tidal, wind, wave, and geothermal. In addition, it explains the underlying physical and technological principles of renewable energy and examines the environmental impact and prospects of different energy sources. With more than 350 detailed illustrations, more than 50 tables of data, and a wide range of case studies, Renewable Energy, 2/e is an ideal choice for undergraduate courses in energy, sustainable development, and environmental science. New to the Second Edition ·Full-color design ·Updated to reflect developments in technology, policy, attitides ·Complemented by Energy Systems and Sustainability edited by Godfrey Boyle, Bob Everett and Janet Ramage, all of the Open University, U.K.

  17. Energy generator

    SciTech Connect

    Krisko, P.

    1989-08-01

    The patent describes a power booster. It comprises: at least one pendulum means suspended at one end to oscillate about the point of suspension; power generating means; mass means connected to one end of the pendulum means; spring means disposed in operative cooperation with the mass means to impart energy into the pendulum means and assist the pendulum means in oscillating about the point of suspension; and energy transfer linkage means between the pendulum means and the power generating means for transferring energy between the pendulum means and the power generating means.

  18. Energy Bingo.

    ERIC Educational Resources Information Center

    Canipe, Stephen

    Rules are provided for this bingo game focusing on terms related to solar, coal, nuclear, hydro, and wind energy. Playing cards and calling cards (to be cut out by the teacher) are also provided. (JN)

  19. Salinity Energy.

    ERIC Educational Resources Information Center

    Schmitt, Walter R.

    1987-01-01

    Discussed are the costs of deriving energy from the earth's natural reserves of salt. Argues that, as fossil fuel supplies become more depleted in the future, the environmental advantages of salinity power may prove to warrant its exploitation. (TW)

  20. Tidal Energy.

    ERIC Educational Resources Information Center

    Impact of Science on Society, 1987

    1987-01-01

    States that tidal power projects are feasible in a relatively limited number of locations around the world. Claims that together they could theoretically produce the energy equivalent to more than one million barrels of oil per year. (TW)

  1. Solar Energy

    ERIC Educational Resources Information Center

    Building Design and Construction, 1977

    1977-01-01

    Describes 21 completed projects now using solar energy for heating, cooling, or electricity. Included are elementary schools in Atlanta and San Diego, a technical school in Detroit, and Trinity University in San Antonio, Texas. (MLF)

  2. Energy Storage

    SciTech Connect

    Mukundan, Rangachary

    2014-09-30

    Energy storage technology is critical if the U.S. is to achieve more than 25% penetration of renewable electrical energy, given the intermittency of wind and solar. Energy density is a critical parameter in the economic viability of any energy storage system with liquid fuels being 10 to 100 times better than batteries. However, the economical conversion of electricity to fuel still presents significant technical challenges. This project addressed these challenges by focusing on a specific approach: efficient processes to convert electricity, water and nitrogen to ammonia. Ammonia has many attributes that make it the ideal energy storage compound. The feed stocks are plentiful, ammonia is easily liquefied and routinely stored in large volumes in cheap containers, and it has exceptional energy density for grid scale electrical energy storage. Ammonia can be oxidized efficiently in fuel cells or advanced Carnot cycle engines yielding water and nitrogen as end products. Because of the high energy density and low reactivity of ammonia, the capital cost for grid storage will be lower than any other storage application. This project developed the theoretical foundations of N2 catalysis on specific catalysts and provided for the first time experimental evidence for activation of Mo 2N based catalysts. Theory also revealed that the N atom adsorbed in the bridging position between two metal atoms is the critical step for catalysis. Simple electrochemical ammonia production reactors were designed and built in this project using two novel electrolyte systems. The first one demonstrated the use of ionic liquid electrolytes at room temperature and the second the use of pyrophosphate based electrolytes at intermediate temperatures (200 – 300 ºC). The mechanism of high proton conduction in the pyrophosphate materials was found to be associated with a polyphosphate second phase contrary to literature claims and ammonia production rates as high as 5X 10

  3. Thermionic Energy

    NASA Technical Reports Server (NTRS)

    1985-01-01

    Thermionic energy conversion is the production of energy from a nuclear source. It is a technology advanced by SNSO, a joint research and development organization formed by NASA and the AEC. SNSO contracted with Thermo Electron Corporation to develop high temperature applications, i.e., metals with high melting points. Thermo Electron Corporation's expertise resulted in contracts for products made from exotic metals such as bone implants, artificial hips, and heart pacemakers.

  4. Energy 101: Clean Energy Manufacturing

    SciTech Connect

    2015-07-09

    Most of us have a basic understanding of manufacturing. It's how we convert raw materials, components, and parts into finished goods that meet our essential needs and make our lives easier. But what about clean energy manufacturing? Clean energy and advanced manufacturing have the potential to rejuvenate the U.S. manufacturing industry and open pathways to increased American competitiveness. Watch this video to learn more about this exciting movement and to see some of these innovations in action.

  5. Geothermal energy

    NASA Astrophysics Data System (ADS)

    Manzella, A.

    2015-08-01

    Geothermal technologies use renewable energy resources to generate electricity and direct use of heat while producing very low levels of greenhouse-gas (GHG) emissions. Geothermal energy is stored in rocks and in fluids circulating in the underground. Electricity generation usually requires geothermal resources temperatures of over 100°C. For heating, geothermal resources spanning a wider range of temperatures can be used in applications such as space and district heating (and cooling, with proper technology), spa and swimming pool heating, greenhouse and soil heating, aquaculture pond heating, industrial process heating and snow melting. Geothermal technology, which has focused so far on extracting naturally heated steam or hot water from natural hydrothermal reservoirs, is developing to more advanced techniques to exploit the heat also where underground fluids are scarce and to use the Earth as a potential energy battery, by storing heat. The success of the research will enable energy recovery and utilization from a much larger fraction of the accessible thermal energy in the Earth's crust.

  6. Energy Conservation

    SciTech Connect

    Simpson, P.

    1995-06-01

    There are two fundamental reasons or motivations for energy conservation: (1) economics; and (2) consideration of energy - its sources and availability. Economics speaks for itself and needs little explanation: a project is undertaken, the cost is recovered in a given period of time (we hope) and our company realizes cost savings thereafter. We study and propose a project; we estimate the payback. If approved, we implement the project. Then, we eagerly watch for its effectiveness - for the proposed payback. The second consideration in regard to energy conservation might - in the foreseeable future - become by far the most important - that of availability. Very knowledgeable persons have stated that this - in reality - is the most serious problem facing our nation today. Readily available, reasonably priced energy has given to the US the high form of living experienced today. An interruption in this flow could catapult our nation in an awesome catastrophe. The energy shortage of the late 70`s might be a forerunner of such an experience.

  7. Energy Deskbook

    SciTech Connect

    Glasstone, S

    1982-06-01

    The purpose of the Energy Deskbook is to serve as a convenient reference to definitions of energy-related terms and descriptions of current and potential energy sources and their utilization. The material is presented at a low technical level with emphasis on general principles, which are not difficult to understand, rather than technology. The entries vary in length from a few lines to several pages, according to circumstances. As a general rule, each topic is defined and outlined in the first paragraph; this may be followed by a more detailed treatment, as required. An important feature of the Deskbook is the use of boldface (heavy) type for cross references. Words in the text set in boldface are the titles of articles where the particular subjects are described.

  8. The Energy Crisis and Solar Energy

    ERIC Educational Resources Information Center

    Bockris, J. O'M.

    1974-01-01

    Examines the status of the energy crisis in Australia. Outlines energy alternatives for the 1990's and describes the present status of solar energy research and the economics of solar energy systems. (GS)

  9. Heavy ion fusion half year report, October 1, 1984-March 30, 1985

    SciTech Connect

    Not Available

    1985-06-01

    Summaries of research are given for each of the following experiments: (1) MBE-4: a four-beam induction linac experiment, (2) performance of the MBE-4 injector, (3) design procedure for acceleration and bunching in an induction linac, (4) longitudinal dynamics of MBE-4, (5) transverse beam dynamics, (6) envelope functions of high-current beam, (7) electrostatic energy analyzer, (8) longitudinal beam control, (9) a capacitive beam-charge monitor for SBTE, (10) materials R and D, (11) simulations of Robertson's lens, and (12) SBTE high sigma/sub 0/ high-current stability limits. (MOW)

  10. Moving Energy

    SciTech Connect

    Rameau, Jon; Crabtree, George; Greene, Laura; Kwok, Wai; Johnson, Peter; Tsvelik, Alexei

    2013-07-18

    Representing the Center for Emergent Superconductivity (CES), this document is one of the entries in the Ten Hundred and One Word Challenge. As part of the challenge, the 46 Energy Frontier Research Centers were invited to represent their science in images, cartoons, photos, words and original paintings, but any descriptions or words could only use the 1000 most commonly used words in the English language, with the addition of one word important to each of the EFRCs and the mission of DOE: energy. The mission of the CES is to discover new high-temperature superconductors and improve the performance of known superconductors by understanding the fundamental physics of superconductivity.

  11. Creating Energy.

    ERIC Educational Resources Information Center

    Wilson, David A.

    The author of this booklet is an engineer who conducts experiments in solar energy. Here he has described basic principles of the field. He also details methods of constructing a variety of solar implements, including solar panels, solar cells, a concentrating collector and a solar furnace. The book is intended for the layman and contains…

  12. Energy politics

    NASA Astrophysics Data System (ADS)

    McEvoy, Augustin

    2012-07-01

    In his review of Tyler Hamilton's book Mad Like Tesla (May pp44-45), Roger Bridgman writes that "in energy supply, obviously, companies cannot simply junk huge infrastructure investments in favour of something new, however good it might be". But that is exactly what Angela Merkel's administration has done in Germany with its anti-nuclear policy.

  13. Energy Theme.

    ERIC Educational Resources Information Center

    Garrahy, Dennis J.

    One of a series of social studies units designed to develop the reading and writing skills of low achievers, this student activity book focuses on the theme of energy. The unit can be used for high school classes, individual study in alternative and continuing high schools, and adult education classes. Separate sections cover early sources of…

  14. Energy Research

    ERIC Educational Resources Information Center

    Group of Eight (NJ1), 2010

    2010-01-01

    The Group of Eight (Go8) is a coalition of leading Australian universities, intensive in research and comprehensive in general and professional education. The Go8 member universities recognise that the issue of energy usage and transformation is one of vital importance not only to Australia but to the world as a whole. The universities aim to make…

  15. Energy Materials.

    ERIC Educational Resources Information Center

    Iowa State Dept. of Public Instruction, Des Moines.

    These resource materials, developed for use by teachers in the elementary and secondary schools, are designed to provide the teacher with a bibliography, questions and answeres, and suggested classroom activities all relating to the energy problem. The materials are designed to develop a conservation ethic and greater understanding of our energy…

  16. Annual Energy Review, 2008

    SciTech Connect

    2009-06-01

    The Annual Energy Review (AER) is the Energy Information Administration's (EIA) primary report of annual historical energy statistics. For many series, data begin with the year 1949. Included are statistics on total energy production, consumption, trade, and energy prices; overviews of petroleum, natural gas, coal, electricity, nuclear energy, renewable energy, and international energy; financial and environment indicators; and data unit conversions.

  17. Energy Recovery

    NASA Astrophysics Data System (ADS)

    1987-01-01

    The United States and other countries face the problem of waste disposal in an economical, environmentally safe manner. A widely applied solution adopted by Americans is "waste to energy," incinerating the refuse and using the steam produced by trash burning to drive an electricity producing generator. NASA's computer program PRESTO II, (Performance of Regenerative Superheated Steam Turbine Cycles), provides power engineering companies, including Blount Energy Resources Corporation of Alabama, with the ability to model such features as process steam extraction, induction and feedwater heating by external sources, peaking and high back pressure. Expansion line efficiency, exhaust loss, leakage, mechanical losses and generator losses are used to calculate the cycle heat rate. The generator output program is sufficiently precise that it can be used to verify performance quoted in turbine generator supplier's proposals.

  18. Cold energy

    SciTech Connect

    Wallace, John P.

    2015-12-04

    Deviations in Q for resonant superconducting radio frequency niobium accelerator cavities are generally correlated with resistivity loss mechanisms. Field dependent Qs are not well modeled by these classical loss mechanisms, but rather can represent a form of precision cavity surface thermometry. When the field dependent Q variation shows improvement with increasing B field level the classical treatment of this problem is inadequate. To justify this behavior hydrogen as a ubiquitous impurity in niobium, which creates measurable property changes, even at very low concentrations is typically considered the cause of such anomalous behavior. This maybe the case in some instances, but more importantly any system operating with a highly coherent field with a significant time dependent magnetic component at near 2° K will have the ability to organize the remaining free spins within the London penetration depth to form a coupled energy reservoir in the form of low mass spin waves. The niobium resonant cavities are composed of a single isotope with a large nuclear spin. When the other loss mechanisms are stripped away this may be the gain medium activated by the low level residual magnetic fields. It was found that one resonant cavity heat treatment produced optimum surface properties and then functioned as a MASER extracting energy from the 2° K thermal bath while cooling the cavity walls. The cavity operating in this mode is a simulator of what can take place in the wider but not colder universe using the cosmic microwave background (CMB) as a thermal source. The low mass, long lifetimes, and the scale of the magnetic spin waves on the weakly magnetized interstellar medium allows energy to be stored that is many orders of magnitude colder than the cosmic microwave background. A linear accelerator cavity becomes a tool to explore the properties of the long wave length magnetic spin waves that populate this cold low energy regime.

  19. Cold energy

    NASA Astrophysics Data System (ADS)

    Wallace, John P.

    2015-12-01

    Deviations in Q for resonant superconducting radio frequency niobium accelerator cavities are generally correlated with resistivity loss mechanisms. Field dependent Qs are not well modeled by these classical loss mechanisms, but rather can represent a form of precision cavity surface thermometry. When the field dependent Q variation shows improvement with increasing B field level the classical treatment of this problem is inadequate. To justify this behavior hydrogen as a ubiquitous impurity in niobium, which creates measurable property changes, even at very low concentrations is typically considered the cause of such anomalous behavior. This maybe the case in some instances, but more importantly any system operating with a highly coherent field with a significant time dependent magnetic component at near 2° K will have the ability to organize the remaining free spins within the London penetration depth to form a coupled energy reservoir in the form of low mass spin waves. The niobium resonant cavities are composed of a single isotope with a large nuclear spin. When the other loss mechanisms are stripped away this may be the gain medium activated by the low level residual magnetic fields. It was found that one resonant cavity heat treatment produced optimum surface properties and then functioned as a MASER extracting energy from the 2° K thermal bath while cooling the cavity walls. The cavity operating in this mode is a simulator of what can take place in the wider but not colder universe using the cosmic microwave background (CMB) as a thermal source. The low mass, long lifetimes, and the scale of the magnetic spin waves on the weakly magnetized interstellar medium allows energy to be stored that is many orders of magnitude colder than the cosmic microwave background. A linear accelerator cavity becomes a tool to explore the properties of the long wave length magnetic spin waves that populate this cold low energy regime.

  20. MBE growth technology for high quality strained III-V layers

    NASA Technical Reports Server (NTRS)

    Grunthaner, Frank J. (Inventor); Liu, John K. (Inventor); Hancock, Bruce R. (Inventor)

    1990-01-01

    The III-V films are grown on large automatically perfect terraces of III-V substrates which have a different lattice constant, with temperature and Group III and V arrival rates chosen to give a Group III element stable surface. The growth is pulsed to inhibit Group III metal accumulation of low temperature, and to permit the film to relax to equilibrium. The method of the invention: (1) minimizes starting step density on sample surface; (2) deposits InAs and GaAs using an interrupted growth mode (0.25 to 2 monolayers at a time); (3) maintains the instantaneous surface stoichiometry during growth (As-stable for GaAs, In-stable for InAs); and (4) uses time-resolved RHEED to achieve aspects (1) through (3).

  1. Sb-based IR photodetector epiwafers on 100 mm GaSb substrates manufactured by MBE

    NASA Astrophysics Data System (ADS)

    Fastenau, Joel M.; Lubyshev, Dmitri; Qiu, Yueming; Liu, Amy W. K.; Koerperick, Edwin J.; Olesberg, Jon T.; Norton, Dennis

    2013-07-01

    Antimony-based materials continue to provide great interest for infrared photodetector and focal plane array imaging applications. Detector architectures include InAs/Ga(In)Sb strained-layer superlattices, which create a type-II band alignment that can be tailored to cover a wide range of the mid- and long-wavelength bands by varying the thickness and composition of the constituent materials, and bulk InAsSb-based XBn barrier designs. These materials can provide desirable detector features such as wider wavelength range, suppression of tunneling currents, improved quantum efficiency, and higher operating temperatures. In order to bring these advantages to market, a reliable manufacturing process must be established on large diameter substrates. We report our latest work on the molecular beam epitaxy growth of Sb-detector epiwafers on 100 mm diameter GaSb substrates in a multi-wafer production format. The growth process has been established to address the challenges of these demanding structures, including the large numbers of alternating thin layers and mixed group-V elements. Various characterization techniques demonstrate excellent surface morphology, crystalline structure quality, and optical properties of the epiwafers. The measured wafer-to-wafer consistency and cross-wafer uniformity demonstrate the potential for volume manufacturing.

  2. Device Fabrication using Crystalline CdTe and CdTe Ternary Alloys Grown by MBE

    SciTech Connect

    Zaunbrecher, Katherine; Burst, James; Seyedmohammadi, Shahram; Malik, Roger; Li, Jian V.; Gessert, Timothy A.; Barnes, Teresa

    2015-06-14

    We fabricated epitaxial CdTe:In/CdTe:As homojunction and CdZnTe/CdTe and CdMgTe/CdTe heterojunction devices grown on bulk CdTe substrates in order to study the fundamental device physics of CdTe solar cells. Selection of emitter-layer alloys was based on passivation studies using double heterostructures as well as band alignment. Initial results show significant device integration challenges, including low dopant activation, high resistivity substrates and the development of low-resistance contacts. To date, the highest open-circuit voltage is 715 mV in a CdZnTe/CdTe heterojunction following anneal, while the highest fill factor of 52% was attained in an annealed CdTe homojunction. In general, all currentvoltage measurements show high series resistance, capacitancevoltages measurements show variable doping, and quantum efficiency measurements show low collection. Ongoing work includes overcoming the high resistance in these devices and addressing other possible device limitations such as non-optimum junction depth, interface recombination, and reduced bulk lifetime due to structural defects.

  3. MBE growth technology for high quality strained III-V layers

    NASA Technical Reports Server (NTRS)

    Grunthaner, Frank J. (Inventor); Liu, John K. (Inventor); Hancock, Bruce R. (Inventor)

    1992-01-01

    III-V films are grown on large automatically perfect terraces of III-V substrates which have a different lattice constant, with temperature and Group II and V arrival rates chosen to give a Group III element stable surface. The growth is pulsed to inhibit Group III metal accumulation to low temperature, and to permit the film to relax to equilibrium. The method of the invention 1) minimizes starting step density on sample surface; 2) deposits InAs and GaAs using an interrupted growth mode (0.25 to 2 mono-layers at a time); 3) maintains the instantaneous surface stoichiometry during growth (As-stable for GaAs, In-stable for InAs); and 4) uses time-resolved RHEED to achieve aspects (1)-14 (3).

  4. Space-charge behavior of 'Thin-MOS' diodes with MBE-grown silicon films

    NASA Technical Reports Server (NTRS)

    Lieneweg, U.; Bean, J. C.

    1984-01-01

    Basic theoretical and experimental characteristics of a novel 'Thin-MOS' technology, which has promising aspects for integrated high-frequency devices up to several hundred gigahertz are presented. The operation of such devices depends on charge injection into undoped silicon layers of about 1000-A thickness, grown by molecular beam epitaxy on heavily doped substrates, and isolation by thermally grown oxides of about 100-A thickness. Capacitance-voltage characteristics measured at high and low frequencies agree well with theoretical ones derived from uni and ambipolar space-charge models. It is concluded that after oxidation the residual doping in the epilayer is less than approximately 10 to the 16th/cu cm and rises by 3 orders of magnitude at the substrate interface within less than 100 A and that interface states at the oxide interface can be kept low.

  5. MBE growth of self-assisted InAs nanowires on graphene

    NASA Astrophysics Data System (ADS)

    Kang, Jung-Hyun; Ronen, Yuval; Cohen, Yonatan; Convertino, Domenica; Rossi, Antonio; Coletti, Camilla; Heun, Stefan; Sorba, Lucia; Kacman, Perla; Shtrikman, Hadas

    2016-11-01

    Self-assisted growth of InAs nanowires on graphene by molecular beam epitaxy is reported. Nanowires with diameter of ∼50 nm and aspect ratio of up to 100 were achieved. The morphological and structural properties of the nanowires were carefully studied by changing the substrate from bilayer graphene through buffer layer to quasi-free-standing monolayer graphene. The positional relation of the InAs NWs with the graphene substrate was determined. A 30° orientation configuration of some of the InAs NWs is shown to be related to the surface corrugation of the graphene substrate. InAs NW-based devices for transport measurements were fabricated, and the conductance measurements showed a semi-ballistic behavior. In Josephson junction measurements in the non-linear regime, multiple Andreev reflections were observed, and an inelastic scattering length of about 900 nm was derived.

  6. Plasma-assisted MBE growth of nitride-based intersubband detectors

    SciTech Connect

    Monroy, Eva; Guillot, Fabien; Leconte, Sylvain; Bellet-Amalric, Edith

    2007-04-10

    In this work, we present the plasma-assisted molecular-beam epitaxy of quantum well infrared photodetector structures, including the Si-doped GaN/AlN short-period superlattice of the active region, AlGaN claddings and integration of the final device. Photovoltage measurements of complete devices reveal a narrow ({approx}90 meV) detection peak at 1.39 {mu}m at room temperature.

  7. Correlation of the MBE growth temperature, material quality, and performance of quantum cascade lasers

    NASA Astrophysics Data System (ADS)

    Monastyrskyi, G.; Aleksandrova, A.; Elagin, M.; Semtsiv, M. P.; Masselink, W. T.; Bryksa, V.

    2013-09-01

    The influence of substrate temperature during the growth of quantum-cascade lasers using gas-source molecular-beam epitaxy on performance and crystal quality of quantum-cascade laser is investigated. Lower substrate temperature is consistently resulting in narrower X-ray diffraction satellites, and lower laser threshold current. This correlation is attributed to increased interface roughness at higher growth temperature.

  8. Formation of pyramid-like nanostructures in MBE grown Si films on Si(001)

    SciTech Connect

    Galiana, Natalia; Martin, Pedro-Pablo; Garzon, L.; Rodriguez-Cañas, E.; Munuera, Carmen; Esteban-Betegon, F.; Varela del Arco, Maria; Ocal, Carmen; Alonso, Maria; Ruiz, Ana

    2010-01-01

    The growth of Si homoepitaxial layers on Si(001) substrates by molecular beam epitaxy is analyzed for a set of growth conditions in which diverse nanometric scale features develop. Using Si substrates prepared by exposure to HF vapor and annealing in ultra high vacuum, a rich variety of surface morphologies is found for different deposited layer thicknesses and substrate temperatures in a reproducible way, showing a critical dependence on both. Arrays of 3D islands (truncated pyramids), percolated ridge networks and square pit (inverted pyramids) distributions are observed. We analyze the obtained arrangements and find remarkable similarities to other semiconductor though heteroepitaxial systems. The nano-scale entities (islands or pits) display certain self assembly and ordering, concerning size, shape and spacing. Film growth sequence follows the islands-coalescence-2D growth pathway, eventually leading to optimum flat morphologies for high enough thickness and temperature.

  9. Features of SOI substrates heating in MBE growth process obtained by low-coherence tandem interferometry

    NASA Astrophysics Data System (ADS)

    Volkov, P. V.; Goryunov, A.. V.; Lobanov, D. N.; Luk'yanov, A. Yu.; Novikov, A. V.; Tertyshnik, A. D.; Shaleev, M. V.; Yurasov, D. V.

    2016-08-01

    Differences in heating of silicon and silicon-on-insulator (SOI) substrates in molecular beam epitaxy were revealed by low-coherence tandem interferometry. Using this technique the interference effects which impede the correct evaluation of SOI substrate temperature by infrared pyrometers can be eliminated and so the reliable temperature readout can be achieved. It was shown that at the same thermocouple and heater power settings the real temperature of SOI substrates is higher than of silicon ones and the difference may be as high as 40-50 °C at temperatures close to 600 °C. It is supposed that such effect is caused by the additional absorption of heater radiation by the buried oxide layer in the mid-infrared range. Independent proof of this effect was obtained by growing on both types of substrates a series of structures with self-assembled Ge nanoislands whose parameters are known to be very temperature sensitive. The proposed low-coherence interferometry technique provides precise real-time control of the growth temperature and so allows formation of SiGe nanostructures with desired parameters.

  10. The MBE growth and optimization of high performance terahertz frequency quantum cascade lasers.

    PubMed

    Li, L H; Zhu, J X; Chen, L; Davies, A G; Linfield, E H

    2015-02-01

    The technique of molecular beam epitaxy has recently been used to demonstrate the growth of terahertz frequency GaAs/AlGaAs quantum cascade lasers (QCL) with Watt-level optical output powers. In this paper, we discuss the critical importance of achieving accurate layer thicknesses and alloy compositions during growth, and demonstrate that precise growth control as well as run-to-run growth reproducibility is possible. We also discuss the importance of minimizing background doping level in maximizing QCL performance. By selecting high-performance active region designs, and optimizing the injection doping level and device fabrication, we demonstrate total optical (two-facet) output powers as high as 1.56 W.

  11. Development of MBE II-VI Epilayers on GaAs(211)B

    NASA Astrophysics Data System (ADS)

    Jacobs, R. N.; Nozaki, C.; Almeida, L. A.; Jaime-Vasquez, M.; Lennon, C.; Markunas, J. K.; Benson, D.; Smith, P.; Zhao, W. F.; Smith, D. J.; Billman, C.; Arias, J.; Pellegrino, J.

    2012-10-01

    Large-area, low-cost substrates are envisioned for next-generation HgCdTe infrared focal-plane arrays (IRFPA). Si, GaAs, Ge, and InSb have been previously examined as potential candidates. Fabrication of IRFPAs based on these substrates is limited by fundamental materials properties that potentially lead to lower detector performance and operability. Lattice and thermal mismatch between the substrate and epilayer are just two of several material factors that must be considered. We have reviewed these factors in the context of more recent data, and determined it worthwhile to revisit the use of GaAs substrates for epitaxial growth of HgCdTe. Our study starts with an evaluation of the surface quality (epireadiness) of commercially available (211) B-oriented GaAs substrates. Molecular beam epitaxial growth of CdTe buffer layers and subsequent HgCdTe absorber layers are performed in separate vacuum-interconnected chambers. The importance of optimization of the CdTe buffer layer growth for high-quality HgCdTe is detailed through surface morphology and x-ray studies. x-Ray diffraction rocking-curve full-width at half-maximum values as low as 52 arcsec have been obtained. Long-wave infrared Hg1- x Cd x Te ( x = 0.23) has been grown on these buffer layers, producing cross-hatch-dominated surface morphologies, with dislocation densities as low as ˜3 × 106 cm-2. We have also obtained (for optimized layers), 80-K Hall-effect n-type carrier concentration and electron mobility of approximately ~1.5 × 1015 cm-3 and 1 × 105 cm2 V-1 s-1, respectively. Finally, we briefly compare GaAs and Si in light of our preliminary investigation.

  12. Low temperature magnetoresistance studies in MBE grown topological insulator thin films

    NASA Astrophysics Data System (ADS)

    Dey, Rik; Roy, Anupam; Pramanik, Tanmoy; Guchhait, Samaresh; Sonde, Sushant; Rai, Amritesh; Majumder, Sarmita; Ghosh, Bahniman; Register, Leonard; Banerjee, Sanjay

    2015-03-01

    We studied low temperature magnetoresistance in molecular beam epitaxy grown topological insulator Bi2Se3andBi2Te3 thin films. The surface and structural characterization of the grown films showed smooth epitaxial growth on Si(111). The magnetoresistance has been measured at low temperatures (2 - 20 K) with magnetic fields upto 9 T. The full range perpendicular field magnetoresistance has been explained with the original Hikami-Larkin-Nagaoka theory. Altshuler-Aronov theory of localization has been used to understand the full range parallel field magnetoresistance. Various scattering times have been estimated by fitting the magnetoresistance data with the theory. It is shown that the Zeeman effect is not needed to explain the magnetoresistance and has not been considered in the theory either. The angle dependent anisotropic magnetoresistance has also been observed and explained using the above theories. This work is funded by NRI-SWAN.

  13. MBE growth of mid-IR type-II interband laser diodes

    NASA Astrophysics Data System (ADS)

    Schmitz, J.; Mermelstein, C.; Kiefer, R.; Walther, M.; Wagner, J.

    2005-05-01

    We report on molecular beam epitaxial growth and characterization of InAs/GaInSb/InAs/AlGaAsSb type-II miniband-to-bound state W-lasers. Laser core structures were characterized using photoluminescence, high resolution X-ray diffraction and Raman spectroscopy to reveal the best growth conditions. The growth temperature for the laser core was varied in the range between 380 °C and 460 °C and found to be optimal at 420 °C. Optimized laser active regions were embedded between 600 nm AlGaAsSb separate confinement layers which in turn were sandwiched between 1.5 μm thick n- and p-doped Al 0.85Ga 0.15As 0.07Sb 0.93 cladding layers. The upper cladding was capped with a 100 nm p +-GaSb contact layer. The growth temperature of the upper separate confinement and cladding layer was varied between 470 °C and 530 °C to reveal the influence on laser performance. Laser emission is observed near 3.2 μm. Devices with uncoated facets, mounted substrate side down could be operated up to a temperature of 185 K in continuous-wave (cw) mode. Single ended output powers of 144 mW in cw mode and 330 mW in pulsed operation were obtained for a 5-period diode laser structure with HR/AR coated mirror facets at an operation temperature of 110 K.

  14. MBE growth and characterization of 5-{mu}m quantum-cascade lasers

    SciTech Connect

    Mamutin, V. V. Ustinov, V. M.; Boetthcher, J.; Kuenzel, H.

    2010-07-15

    Quantum-cascade lasers, which are obtained by molecular-beam epitaxy, emit at wavelengths of 5.0 {mu}m at 77 K and 5.2 {mu}m at 300 K and are based on a design with four quantum wells in the active region with vertical transitions and strain-compensated superlattices with high-efficiency injection and a short lifetime of the ground state are fabricated. The typical thresholds for lasing at 300 K were in the range 4-10 kA/cm{sup 2}. The maximum emission power was as high as {approx}1 W, the maximum lasing temperature was {approx}450 K, and the maximum characteristic temperature T{sub 0} {approx} 200 K. The use of a modified process of postgrowth treatment made it possible to reproducibly obtain high-quality devices.

  15. Monthly Energy Review

    EIA Publications

    2016-01-01

    The Monthly Energy Review (MER) is the U.S. Energy Information Administration's primary report of recent energy statistics. Included are total energy production, consumption, and trade; energy prices; overviews of petroleum, natural gas, coal, electricity, nuclear energy, renewable energy, and international petroleum; carbon dioxide emissions; and data unit conversions.

  16. Energy management

    SciTech Connect

    Glenn, J.

    1991-10-01

    This paper is a review of the Department of Energy's (DOE) Contractor Purchasing System Review (CPSR) Program, which oversees the extensive subcontracting activities of the Department's management and operating (M and O) contractors. This review is part of a special GAO audit effort to help ensure that areas vulnerable to fraud, waste, abuse, and mismanagement are identified and that adequate corrective actions are taken. This effort focuses on 16 areas, one of which is DOE contractor oversight. This report describes the subcontracting deficiencies occurring at DOE, identifies shortcomings in DOE's CPSR Program, and discusses the corrective actions that DOE has committed to take in its CPSR Program in response to these findings.

  17. Fabrication of precision high quality facets on molecular beam epitaxy material

    DOEpatents

    Petersen, Holly E.; Goward, William D.; Dijaili, Sol P.

    2001-01-01

    Fabricating mirrored vertical surfaces on semiconductor layered material grown by molecular beam epitaxy (MBE). Low energy chemically assisted ion beam etching (CAIBE) is employed to prepare mirrored vertical surfaces on MBE-grown III-V materials under unusually low concentrations of oxygen in evacuated etching atmospheres of chlorine and xenon ion beams. UV-stabilized smooth-surfaced photoresist materials contribute to highly vertical, high quality mirrored surfaces during the etching.

  18. Energy awareness luncheon and energy seminar

    SciTech Connect

    1980-07-23

    A separate abstract was prepared for each of the following: the luncheon address, energy-growth-freedom by Kenneth A. Randall; the keynote commentary, by F.S. Patton, program chairman; and four current-awareness papers on the future of oil and gas, coal, nuclear energy, and solar energy. In addition, in a section, Speaking of Energy, very brief statements by eight professional engineers on the energy challenge are included. Also, the NSPE position paper on energy policy is included.

  19. Energy barriers

    SciTech Connect

    Alvarez, M.

    1991-01-01

    Energy conservation and home insulation may have been off the front pages in recent years, but rising fuel prices and the current crisis in the Mideast remind us once again that it's time to make sure our houses are adequately insulated. Doing so saves money and, to borrow a phrase from that Quaker Oats commercial, It's the right thing to do. Heat always wants to sneak from a warm space to a cold one. In the winter, it's like a convict trying to bust out of the big joint - it looks for any gap, crack or chink that it can slip through. Int he summer, it's more like a burglar trying to break in to your house. Insulation, properly installed, keeps the heat and the cold where you want it. You probably already know that insulation is rated by R-value, which indicates the material's ability to (R)esist the flow of heat. The higher the R-value, the greater the insulating power. But how much is enough The three model national building codes that form the basis for most state and municipal building codes now support a single, recently revised Model Energy Code. This article deals with deciding how much insulation is right for the application and how to install it correctly.

  20. Energy efficiency, renewable energy and sustainable development

    SciTech Connect

    Ervin, C.A.

    1994-12-31

    The Office of Energy Efficiency and Renewable Energy (EE) is part of the U.S. Department of Energy that is specifically charged with encouraging the more efficient use of energy resources, and the use of renewable energy resources - such as solar power, wind power, biomass energy and geothermal energy. In the past several years, EE has increased its emphasis on technology deployment through partnerships with states, local governments and private companies. Partnerships move new discoveries more quickly into the marketplace, where they can create jobs, prevent pollution, save resources, and produce many other benefits. The author then emphasizes the importance of this effort in a number of different sections of the paper: energy consumption pervades everything we do; U.S. energy imports are rising to record levels; transportation energy demand is increasing; U.S. energy use is increasing; population growth increases world energy demand; total costs of energy consumption aren`t always counted; world energy markets offer incredible potential; cost of renewables is decreasing; clean energy is essential to sustainable development; sustainable energy policy; sustainable energy initiatives: utilities, buildings, and transportation.

  1. Energy management

    SciTech Connect

    Dingell, J.D.

    1991-10-01

    In January 1990 GAO began implementing a special audit effort to help ensure that areas vulnerable to fraud, waste, abuse, and mismanagement are identified and that appropriate corrective actions are taken. This effort focuses on 16 areas, one of which is the Department of Energy's (DOE) contracting practices. As part of this effort, the authors determined if contract audits for monitoring and overseeing DOE's contracting process were being performed and that we identify the impact or potential impact to the government when contract audits were not performed. Specifically, this paper discusses audit coverage of DOE's management and operating (M and O) contractors and DOE contracts, the problems that may occur when contract audit activity is not performed, and factors that have impeded contract audit coverage.

  2. Energy and Resources

    ERIC Educational Resources Information Center

    Sorensen, Bent

    1975-01-01

    Discusses the feasibility of utilizing continuous sources of of energy, particularly solar and wind energy. Outlines an energy plan for Denmark, which would supply all of Denmark's energy needs by the year 2050. (MLH)

  3. Cutting Energy Costs.

    ERIC Educational Resources Information Center

    Rittner-Heir, Robbin M.

    2003-01-01

    Describes school-district energy-conservation efforts including teaching students to save energy, retrofitting schools, hiring energy consulting companies, and activating the sleep function on computer monitors. Also describes the federal Energy Star program (www.energystar.gov). (PKP)

  4. Annual energy review 1996

    SciTech Connect

    1997-07-01

    This report presents historical energy statistics on all major energy activities. The statistics cover consumption, production, trade, stock, and prices, for all major energy commodities including fossil fuels, electricity, and renewable energy sources.

  5. Wind energy systems

    NASA Technical Reports Server (NTRS)

    Stewart, H. J.

    1978-01-01

    A discussion on wind energy systems involved with the DOE wind energy program is presented. Some of the problems associated with wind energy systems are discussed. The cost, efficiency, and structural design of wind energy systems are analyzed.

  6. Theme: Energy Education.

    ERIC Educational Resources Information Center

    Kirkland, Joe R.; And Others

    1981-01-01

    This series of articles focuses on energy education as a part of secondary vocational agriculture. Among the topics addressed are alternative energy sources for agriculture, wood power technology, energy efficiency, and energy in the Future Farmers of America program. (LRA)

  7. Seasonal thermal energy storage

    SciTech Connect

    Allen, R.D.; Kannberg, L.D.; Raymond, J.R.

    1984-05-01

    This report describes the following: (1) the US Department of Energy Seasonal Thermal Energy Storage Program, (2) aquifer thermal energy storage technology, (3) alternative STES technology, (4) foreign studies in seasonal thermal energy storage, and (5) economic assessment.

  8. GaSb thermophotovoltaics: current challenges and solutions

    NASA Astrophysics Data System (ADS)

    Rahimi, N.; Herrera, D. J.; Aragon, A.; Shima, D. M.; Romero, O. S.; Rotter, T. J.; Busani, T.; Lavrova, O.; Balakrishnan, G.; Lester, L. F.

    2015-03-01

    GaSb thermophotovoltaic cells fabricated using Molecular Beam Epitaxy (MBE) and ion implantation techniques are studied. Challenges including different defect formation mechanisms using MBE and ion-induced defects using ion implantation were investigated by cross-sectional Transmission Electron Microscopy (XTEM), X-Ray Diffraction spectroscopy (XRD) and Scanning Electron Microscopy (SEM). For MBE grown TPVs, several approaches were used to suppress defects, including substrate preparation and using different MBE reactors. For ion-implanted TPVs, different implant doses and energies were tested to minimize the crystal damage and various Rapid Thermal Anneal (RTA) process recipes were studied to maximize the crystal recovery. Large area TPV cells with 1 × 1 cm dimensions were fabricated using these techniques, then electrically and optically characterized. Ideality factors and dark saturation currents were measured and compared for various TPVs.

  9. Collecting Solar Energy. Solar Energy Education Project.

    ERIC Educational Resources Information Center

    O'Brien, Alexander

    This solar energy learning module for use with junior high school students offers a list of activities, a pre-post test, job titles, basic solar energy vocabulary, and diagrams of solar energy collectors and installations. The purpose is to familiarize students with applications of solar energy and titles of jobs where this knowledge could be…

  10. Energy 101: Energy Efficient Commercial Buildings

    ScienceCinema

    None

    2016-07-12

    Learn how commercial buildings can incorporate whole-building design to save energy and money while enhancing performance and comfort. This video highlights several energy-saving features of the Research Support Facility at the Energy Department's National Renewable Energy Laboratory-a model for high-performance office building design.

  11. Energy 101: Energy Efficient Commercial Buildings

    SciTech Connect

    2014-03-14

    Learn how commercial buildings can incorporate whole-building design to save energy and money while enhancing performance and comfort. This video highlights several energy-saving features of the Research Support Facility at the Energy Department's National Renewable Energy Laboratory-a model for high-performance office building design.

  12. Energy Informatics Panel (Presentation)

    SciTech Connect

    Brodt-Giles, D.

    2012-06-01

    Designed to be the world's most comprehensive, open, and collaborative energy information network, Open Energy Information (OpenEI - openei.org) supplies essential energy data to decision makers and supports a global energy transformation. The platform, sponsored by the U.S. Department of Energy (DOE) and developed by the National Renewable Energy Laboratory (NREL), is intended for global contribution and collaboration.

  13. Energy: The Surprising Decade.

    ERIC Educational Resources Information Center

    Fowler, John M.

    1983-01-01

    Stresses the importance of energy education and discusses various aspects of and trends related to energy in the United States. These include energy costs, recession and energy conservation, the nuclear debate, environmental concerns (including acid rain), solar energy, technological developments, energy policy/politics, and projection of energy…

  14. The ABC's of Energy.

    ERIC Educational Resources Information Center

    Barrow, Lloyd H., Ed.; Bitner, Betty L., Ed.

    This resource guide consists of activities related to 26 separate energy topics (one for each letter of the alphabet). Topic areas are: approaches to problems related to energy shortages; biomass; conserving energy; demand for energy in the year 2000; economics and energy; fossil fuels; geothermal energy; hydroelectric power; insulation; energy…

  15. Tribal Energy Program, Assisting Tribes to Realize Their Energy Visions (Brochure), Energy Efficiency & Renewable Energy (EERE)

    SciTech Connect

    Not Available

    2013-06-01

    This 12-page brochure provides an overview of the U.S. Department of Energy Office of Energy Efficiency and Renewable Energy's Tribal Energy Program and describes the financial, technical, and educational assistance it provides to help tribes develop their renewable energy resources and reduce their energy consumption.

  16. Renewable energy technologies

    SciTech Connect

    Kristoferson, L.A.; Bokalders, V.

    1986-01-01

    This book provides a valuable overview of the prospects for new and renewable energy technologies and their possible role in energy planning in developing countries. Contents include: biomass energy; production; conversion; utilisation; biomass engines and biomass fuels; solar energy systems; wind energy systems; and hydro energy systems.

  17. Arctic Energy Resources: Energy Research

    NASA Astrophysics Data System (ADS)

    Gryc, George

    1984-04-01

    Arctic Energy Resources is a volume of 26 papers recording the proceedings of the Comite' Arctique International Conference, held at the Veritas Centre, Oslo, Norway, September 22-24, 1982. This was the fourth of a series of meetings on the Arctic organized by the Comite', an organization established in the Principality of Monaco with the active support of H.S.H. Prince Rainer III. The fourth Conference was opened by H.R.H. Crown Prins Harald of Norway, a noble beginning for a noble objective.The North Polar Region has drawn world attention recently because of several large hydrocarbon and other mineral discoveries and because of major political and environmental actions in the North American Arctic. Since 1923 when Naval Petroleum Reserve number 4 (NPR-4) was established, northern Alaska has been considered a major petroleum province. It was first explored systematically with modern techniques from 1943 to 1953. In 1958, Alaska became a state, and both federal and state lands in northern Alaska were available for private exploration. Building on the knowledge base provided by the Pet-4 program and its spinoff research laboratory at Barrow, industry explored the area east of NPR-4 and discovered the largest hydrocarbon accumulation (9.6 bbl crude oil and 26 Tcf (trillion cubic feet) gas) in North America at Prudhoe Bay. Concerns for environmental impacts, including oil spills, led to the passing of the National Environmental Policy Act in 1969. In 1970, over 9 million acres were set aside, now known as the Arctic National Wildlife Range, and in 1971 the Alaska Native Claims Settlement Act was passed by the U.S. Congress. The Arab oil embargo of 1973 heightened the energy crisis and changed the economic basis for further exploration in the Arctic. The convergence of these events dramatically changed the balance of power and the pace of activity in the North American Arctic.

  18. Fusion energy

    NASA Astrophysics Data System (ADS)

    1990-09-01

    The main purpose of the International Thermonuclear Experimental Reactor (ITER) is to develop an experimental fusion reactor through the united efforts of many technologically advanced countries. The ITER terms of reference, issued jointly by the European Community, Japan, the USSR, and the United States, call for an integrated international design activity and constitute the basis of current activities. Joint work on ITER is carried out under the auspices of the International Atomic Energy Agency (IAEA), according to the terms of quadripartite agreement reached between the European Community, Japan, the USSR, and the United States. The site for joint technical work sessions is at the Max Planck Institute of Plasma Physics. Garching, Federal Republic of Germany. The ITER activities have two phases: a definition phase performed in 1988 and the present design phase (1989 to 1990). During the definition phase, a set of ITER technical characteristics and supporting research and development (R and D) activities were developed and reported. The present conceptual design phase of ITER lasts until the end of 1990. The objectives of this phase are to develop the design of ITER, perform a safety and environmental analysis, develop site requirements, define future R and D needs, and estimate cost, manpower, and schedule for construction and operation. A final report will be submitted at the end of 1990. This paper summarizes progress in the ITER program during the 1989 design phase.

  19. Photovoltaic energy

    NASA Astrophysics Data System (ADS)

    1990-01-01

    In 1989, the U.S. photovoltaic industry enjoyed a growth rate of 30 percent in sales for the second year in a row. This sends a message that the way we think about electricity is changing. Instead of big energy projects that perpetuate environmental and economic damage, there is a growing trend toward small renewable technologies that are well matched to end-user needs and operating conditions. As demand grows and markets expand, investment capital will be drawn to the industry and new growth trends will emerge. The photovoltaic industry around the world achieved record shipments also. Worldwide shipments of photovoltaic (PV) modules for 1989 totaled more than 40 megawatts (MW), nearly a 20 percent increase over last year's shipments. The previous two years showed increases in worldwide shipments of 23 and 25 percent, respectively. If this growth rate continues through the 1990s, as industry back orders would indicate, 300 to 1000 MW of PV-supplied power could be on line by 2000. Photovoltaic systems have low environmental impact and they are inexpensive to operate and maintain. Using solid-state technology, PV systems directly convert sunlight to electricity without high-temperature fluids or moving parts that could cause mechanical failure. This makes the technology very reliable.

  20. Fusion energy

    SciTech Connect

    Not Available

    1990-09-01

    The main purpose of the International Thermonuclear Experimental Reactor (ITER) is to develop an experimental fusion reactor through the united efforts of many technologically advanced countries. The ITER terms of reference, issued jointly by the European Community, Japan, the USSR, and the United States, call for an integrated international design activity and constitute the basis of current activities. Joint work on ITER is carried out under the auspices of the International Atomic Energy Agency (IAEA), according to the terms of quadripartite agreement reached between the European Community, Japan, the USSR, and the United States. The site for joint technical work sessions is at the MaxPlanck Institute of Plasma Physics. Garching, Federal Republic of Germany. The ITER activities have two phases: a definition phase performed in 1988 and the present design phase (1989--1990). During the definition phase, a set of ITER technical characteristics and supporting research and development (R D) activities were developed and reported. The present conceptual design phase of ITER lasts until the end of 1990. The objectives of this phase are to develop the design of ITER, perform a safety and environmental analysis, develop site requirements, define future R D needs, and estimate cost, manpower, and schedule for construction and operation. A final report will be submitted at the end of 1990. This paper summarizes progress in the ITER program during the 1989 design phase.

  1. Global view of energy

    SciTech Connect

    Kursunoglu, B.N.; Millunzi, A.C.; Perlmutter, A.

    1982-01-01

    This book contains selected papers presented at the fourth interdisciplinary international forum on the Geopolitics of Energy. Topics included: energy demand; energy modeling; urgency of world energy problems; nuclear fission; progress in nuclear fusion; financing energy investments; conservation of energy in developed countries; public safety - risks and benefits; and atmospheric carbon dioxide. A separate abstract was prepared for each of the 25 papers for inclusion in the Energy Data Base; all will appear in Energy Abstracts for Policy Analysis and five in Energy Research Abstracts (ERA). (RJC)

  2. Guam Strategic Energy Plan

    SciTech Connect

    Conrad, M. D.

    2013-07-01

    Describes various energy strategies available to Guam to meet the territory's goal of diversifying fuel sources and reducing fossil energy consumption 20% by 2020.The information presented in this strategic energy plan will be used by the Guam Energy Task Force to develop an energy action plan. Available energy strategies include policy changes, education and outreach, reducing energy consumption at federal facilities, and expanding the use of a range of energy technologies, including buildings energy efficiency and conservation, renewable electricity production, and alternative transportation. The strategies are categorized based on the time required to implement them.

  3. Direct Conversion of Energy.

    ERIC Educational Resources Information Center

    Corliss, William R.

    This publication is one of a series of information booklets for the general public published by the United States Atomic Energy Commission. Direct energy conversion involves energy transformation without moving parts. The concepts of direct and dynamic energy conversion plus the laws governing energy conversion are investigated. Among the topics…

  4. Energy Conservation Simplified

    ERIC Educational Resources Information Center

    Hecht, Eugene

    2008-01-01

    The standard formulation of energy conservation involves the subsidiary ideas of kinetic energy ("KE"), work ("W"), thermal energy, internal energy, and a half-dozen different kinds of potential energy ("PE"): elastic, chemical, nuclear, gravitational, and so forth. These quantities came to be recognized during the centuries over which the…

  5. Monthly Energy Review

    SciTech Connect

    1996-05-28

    This publication presents an overview of the Energy information Administration`s recent monthly energy statistics. The statistics cover the major activities of US production, consumption, trade, stocks, and prices for petroleum, natural gas, coal, electricity, and nuclear energy. Also included are international energy and thermal and metric conversion factors. Two brief ``energy plugs`` (reviews of EIA publications) are included, as well.

  6. Solar energy collector

    DOEpatents

    Brin, Raymond L.; Pace, Thomas L.

    1978-01-01

    The invention relates to a solar energy collector comprising solar energy absorbing material within chamber having a transparent wall, solar energy being transmitted through the transparent wall, and efficiently absorbed by the absorbing material, for transfer to a heat transfer fluid. The solar energy absorbing material, of generally foraminous nature, absorbs and transmits the solar energy with improved efficiency.

  7. The Science of Energy.

    ERIC Educational Resources Information Center

    National Energy Education Development Project, Reston, VA.

    This unit of study for secondary students focuses on energy uses, energy sources, energy forms, and energy conversion. The unit is designed to take five 45-minute class sessions. In the first class session, the teacher conducts several energy conversion experiments. In subsequent sessions, students are divided into seven groups and each is…

  8. Insight: An Energy Curriculum.

    ERIC Educational Resources Information Center

    Kohl, Herb

    1979-01-01

    The author explains some of the activities he uses in his upper elementary energy curriculum when dealing with these topics: the definition of energy; gasoline consumption; energy conversion; solar energy; and the politics of energy. Resource agencies to which students may write for information are listed. (SJL)

  9. Winning the Energy Game.

    ERIC Educational Resources Information Center

    Zielinski, Edward J.; Bethel, Lowell J.

    1983-01-01

    Describes the use of an Energy-Environment Simulator in environmental/energy education programs. The simulator is a specially designed analog computer that simulates real-world conditions of energy production and use. Energy resources, demands, and the environmental effects of energy use are programmed into the computer. (Author/JN)

  10. Energy Production Systems. Energy Technology Series.

    ERIC Educational Resources Information Center

    Center for Occupational Research and Development, Inc., Waco, TX.

    This course in energy production systems is one of 15 courses in the Energy Technology Series developed for an Energy Conservation-and-Use Technology curriculum. Intended for use in two-year postsecondary technical institutions to prepare technicians for employment, the courses are also useful in industry for updating employees in…

  11. Forget energy conservation - think energy efficiency

    SciTech Connect

    Decker, D.A.

    1996-12-31

    {open_quotes}CONSERVE ENERGY: Please Turn Off The Lights!{close_quotes} Many buildings constructed before 1975 have the peeling remains of those green or orange stickers on light switches. They are the remnants of a U.S. energy policy gone bad. Twenty years ago, energy conservation meant telling employees to wear sweaters to work and applying stickers to remind people to turn off the lights. Neither worked. People who see those old stickers probably don`t know that a quiet revolution has taken place inside thousands of public and commercial buildings. Thanks to new technology and a new attitude about energy, you can forget sweaters and switches. For example... (1) Motion sensors automatically turn off fights when you leave the room. (2) Computers determine when energy rates go down to get the best value. (3) Personal environmental modules let office workers set their cubicle`s heating and lighting levels. These days, energy efficiency is equated with good business. It can increase productivity, create jobs, and reduce pollution -- all with very little effort. That`s why it`s called energy efficiency, not energy conservation. And energy efficiency is good government. If Congress truly is committed to lowering taxes and reducing the budget deficit, members should first look at ways to lower the nation`s energy bill through energy efficiency. It is in the best interests of the energy efficiency industry to work together and promote these benefits.

  12. Representing Energy. II. Energy Tracking Representations

    ERIC Educational Resources Information Center

    Scherr, Rachel E.; Close, Hunter G.; Close, Eleanor W.; Vokos, Stamatis

    2012-01-01

    The Energy Project at Seattle Pacific University has developed representations that embody the substance metaphor and support learners in conserving and tracking energy as it flows from object to object and changes form. Such representations enable detailed modeling of energy dynamics in complex physical processes. We assess student learning by…

  13. Science Activities in Energy: Electrical Energy.

    ERIC Educational Resources Information Center

    Oak Ridge Associated Universities, TN.

    Presented is a science activities in energy package which includes 16 activities relating to electrical energy. Activities are simple, concrete experiments for fourth, fifth and sixth grades which illustrate principles and problems relating to energy. Each activity is outlined in a single card which is introduced by a question. A teacher's…

  14. Science Activities in Energy: Solar Energy.

    ERIC Educational Resources Information Center

    Oak Ridge Associated Universities, TN.

    Presented is a science activities in energy package which includes 12 activities relating to solar energy. Activities are simple, concrete experiments for fourth, fifth, and sixth grades, which illustrate principles and problems relating to energy. Each activity is outlined on a single card which is introduced by a question. A teacher's supplement…

  15. Science Activities in Energy: Chemical Energy.

    ERIC Educational Resources Information Center

    Oak Ridge Associated Universities, TN.

    Presented is a science activities in energy package which includes 15 activities relating to chemical energy. Activities are simple, concrete experiments for fourth, fifth and sixth grades which illustrate principles and problems relating to energy. Each activity is outlined on a single card which is introduced by a question. A teacher's…

  16. Fission Energy and Other Sources of Energy

    ERIC Educational Resources Information Center

    Alfven, Hannes

    1974-01-01

    Discusses different forms of energy sources and basic reasons for the opposition to the use of atomic energy. Suggests that research efforts should also be aimed toward the fission technology to make it acceptable besides major research studies conducted in the development of alternative energy sources. (CC)

  17. Smoothness and cleanliness of the GaAs (100) surface after thermal desorption of the native oxide for the synthesis of high mobility structures using molecular beam epitaxy

    NASA Astrophysics Data System (ADS)

    Lee, J. J. D.; West, K. W.; Baldwin, K. W.; Pfeiffer, L. N.

    2012-10-01

    To prepare a GaAs substrate for molecular beam epitaxial (MBE) growth, the nominal ˜3 nm native oxide is typically thermally desorbed into vacuum. To test the completeness and quality of this desorption, we describe a technique, which combines MBE, thermal desorption, atomic force microscopy (AFM), reflection high-energy electron diffraction (RHEED), and secondary ion mass spectroscopy (SIMS), for detecting roughness and trace residues of contamination on (100) GaAs surfaces before MBE growth. At all desorption temperatures in the range 600-665 °C, our RHEED measurements show that the native oxide is largely desorbed within 4 min. However, the SIMS and AFM data indicate that a residue of carbon invariably remains on the GaAs (100) surface, and tenaciously resists all further attempts at its removal by thermal desorption. Since thermal desorption of the native oxide has long been the standard technique for preparing GaAs substrates for MBE growth, we suggest that MBE growth on GaAs has in general been accomplished by epitaxially growing through a partial monolayer of carbon. We believe this is the likely reason for the generally unsatisfactory quality of GaAs MBE growth after lithographic patterning on previously MBE grown structures. Our AFM data also indicate that extended native oxide desorption times or high desorption temperatures not only are ineffective at removal of the carbon residue, but are always accompanied by additional strong roughening effects on the GaAs surface morphology. Finally, we demonstrate that smoother starting surfaces for MBE growth correlate well with higher two-dimensional carrier mobilities in the resulting AlGaAs/GaAs heterostructures.

  18. Energy Use in Manufacturing

    EIA Publications

    2006-01-01

    This report addresses both manufacturing energy consumption and characteristics of the manufacturing economy related to energy consumption. In addition, special sections on fuel switching capacity and energy-management activities between 1998 and 2002 are also featured in this report.

  19. Charging graphene for energy

    NASA Astrophysics Data System (ADS)

    Liu, Jun

    2014-10-01

    Energy storage is a grand challenge for future energy infrastructure, transportation and consumer electronics. Jun Liu discusses how graphene may -- or may not -- be used to improve various electrochemical energy storage devices.

  20. The Energy Crisis

    ERIC Educational Resources Information Center

    Sandercock, Ted

    1973-01-01

    Discusses the nature of energy, the ways in which it is used in our society, non-polluting sources of energy, and means by which energy can be conserved to alleviate the shortage and minimize environmental degradation. (JR)

  1. Alcohol Energy Drinks

    MedlinePlus

    ... Home / About Addiction / Alcohol / Alcohol Energy Drinks Alcohol Energy Drinks Read 17728 times font size decrease font size increase font size Print Email Alcohol energy drinks (AEDs) or Caffeinated alcoholic beverages (CABs) are ...

  2. Save Energy Now Resources

    SciTech Connect

    2008-03-01

    The U.S. Department of Energy (DOE) provides information resources to industrial energy users and partnering organizations to help the nation’s industrial sector save energy and improve productivity.

  3. Some Myths Surrounding Energy.

    ERIC Educational Resources Information Center

    Beynon, John

    1990-01-01

    Energy as an abstract concept is discussed, and the effect of using inappropriate language in the teaching of energy is considered. The storage of energy is illustrated using gravitation and the combustion of coal as examples. (CW)

  4. Energy for Mankind

    ERIC Educational Resources Information Center

    Pincherle, L.; Rice-Evans, P.

    1977-01-01

    Discusses statistics concerning world energy requirements and supplies of different types of fuels. Also discusses the storage and transmission of energy and pollution problems related to energy utilization. (MLH)

  5. Oneida Tribe Energy Audits

    SciTech Connect

    Olson, Ray; Schubert, Eugene

    2014-08-15

    Project funding energy audits of 44 Tribally owned buildings operated by the Oneida Tribe of Indians of WI. Buildings were selected for their size, age, or known energy concerns and total over 1 million square feet. Audits include feasibility studies, lists of energy improvement opportunities, and a strategic energy plan to address cost effective ways to save energy via energy efficiency upgrades over the short and long term.

  6. Nation's energy dilemma

    SciTech Connect

    Krenz, J.H.

    1981-05-01

    Because we understand production patterns better than energy-use patterns, Americans find it difficult to grasp the significance of resource scarcity and depletion and the need to continue energy inputs to sustain a developed society. Arguments against more-efficient energy use cite cost and life-style disruptions, but these must be weighed against the socio-economic impacts of traditional energy expansion. A new energy consciousness should be applied to investment decisions involving energy to eliminate waste. This will require changes in products, habits, and attitudes. Policies that will develop data and expertise in the thermodynamic principles of energy usage will help to change the way energy is valued. (DCK)

  7. Energy Choices for Consumers

    ERIC Educational Resources Information Center

    Nolan, William T.

    1977-01-01

    Sample problems concerning energy consumption and conservation with air conditioners, electric ranges, refrigerators and televisions are provided. The energy efficiency ratio (EER) is also discussed. (CP)

  8. Three Forms of Energy.

    ERIC Educational Resources Information Center

    Petursson, Sigthor

    2003-01-01

    Identifies practical ways to introduce students to thermodynamic concepts, such as heat and mechanical energy. Introduces three different energy transformations that everyone should be able to envisage. (SOE)

  9. Monthly energy review, July 1993

    SciTech Connect

    Not Available

    1993-07-27

    This publication presents information and compiled data on energy sources. The following information is presented: energy overview; energy consumption; petroleum; natural gas; oil and gas resource development; coal; electricity; nuclear energy; energy prices; and international energy.

  10. Western Energy Corridor -- Energy Resource Report

    SciTech Connect

    Leslie Roberts; Michael Hagood

    2011-06-01

    The world is facing significant growth in energy demand over the next several decades. Strategic in meeting this demand are the world-class energy resources concentrated along the Rocky Mountains and northern plains in Canada and the U.S., informally referred to as the Western Energy Corridor (WEC). The fossil energy resources in this region are rivaled only in a very few places in the world, and the proven uranium reserves are among the world's largest. Also concentrated in this region are renewable resources contributing to wind power, hydro power, bioenergy, geothermal energy, and solar energy. Substantial existing and planned energy infrastructure, including refineries, pipelines, electrical transmission lines, and rail lines provide access to these resources.

  11. Energy planning and energy efficiency assistance

    SciTech Connect

    Markel, L.

    1995-12-31

    Electrotek is an engineering services company specializing in energy-related programs. Clients are most utilities, large energy users, and the U.S. Electric Power Research Institute. Electrotek has directed energy projects for the U.S. Agency for International Development and the U.S. Department of Energy in Poland and other countries of Central Europe. The objective is to assist the host country organizations to identify and implement appropriate energy efficiency and pollution reduction technologies, to transfer technical and organizational knowledge, so that further implementations are market-driven, without needed continuing foreign investment. Electrotek has worked with the Silesian Power Distribution Company to design an energy efficiency program for industrial customers that has proven to be profitable for the company and for its customers. The program has both saved energy and costs, and reduced pollution. The program is expanding to include additional customers, without needing more funding from the U.S. government.

  12. Minority energy assessment report

    SciTech Connect

    Teotia, A.P.S.; Poyer, D.A.; Lampley, L.; Anderson, J.L.

    1992-12-01

    The purpose of this research is to project household energy consumption, energy expenditure, and energy expenditure as share of income for five population groups from 1991 to 2009. The approach uses the Minority Energy Assessment Model (MEAM), developed by Argonne National Laboratory for the US Department of Energy's Office of Minority Economic Impact. The MEAM provides a framework that can be used to forecast regional energy consumption and energy expenditure for majority, black, Hispanic, poor, and nonpoor households. The forecasts of key macroeconomic and energy variables used as exogenous variables in the MEAM were obtained from the Data Resources, Inc., Macromodel and Energy Model. Generally, the projections of household energy consumption, expenditure, and energy expenditure as share of income vary across population groups and census regions.

  13. Geothermal energy program overview

    NASA Astrophysics Data System (ADS)

    1991-12-01

    The mission of the Geothermal Energy Program is to develop the science and technology necessary for tapping our nation's tremendous heat energy sources contained within the Earth. Geothermal energy is a domestic energy source that can produce clean, reliable, cost-effective heat and electricity for our nation's energy needs. Geothermal energy - the heat of the Earth - is one of our nation's most abundant energy resources. In fact, geothermal energy represents nearly 40 percent of the total U.S. energy resource base and already provides an important contribution to our nation's energy needs. Geothermal energy systems can provide clean, reliable, cost-effective energy for our nation's industries, businesses, and homes in the form of heat and electricity. The U.S. Department of Energy's (DOE) Geothermal Energy Program sponsors research aimed at developing the science and technology necessary for utilizing this resource more fully. Geothermal energy originates from the Earth's interior. The hottest fluids and rocks at accessible depths are associated with recent volcanic activity in the western states. In some places, heat comes to the surface as natural hot water or steam, which have been used since prehistoric times for cooking and bathing. Today, wells convey the heat from deep in the Earth to electric generators, factories, farms, and homes. The competitiveness of power generation with lower quality hydrothermal fluids, geopressured brines, hot dry rock, and magma (the four types of geothermal energy), still depends on the technical advancements sought by DOE's Geothermal Energy Program.

  14. Geothermal Energy Program overview

    SciTech Connect

    Not Available

    1991-12-01

    The mission of the Geothermal Energy Program is to develop the science and technology necessary for tapping our nation's tremendous heat energy sources contained with the Earth. Geothermal energy is a domestic energy source that can produce clean, reliable, cost- effective heat and electricity for our nation's energy needs. Geothermal energy -- the heat of the Earth -- is one of our nation's most abundant energy resources. In fact, geothermal energy represents nearly 40% of the total US energy resource base and already provides an important contribution to our nation's energy needs. Geothermal energy systems can provide clean, reliable, cost-effective energy for our nation's industries, businesses, and homes in the form of heat and electricity. The US Department of Energy's (DOE) Geothermal Energy Program sponsors research aimed at developing the science and technology necessary for utilizing this resource more fully. Geothermal energy originates from the Earth's interior. The hottest fluids and rocks at accessible depths are associated with recent volcanic activity in the western states. In some places, heat comes to the surface as natural hot water or steam, which have been used since prehistoric times for cooking and bathing. Today, wells convey the heat from deep in the Earth to electric generators, factories, farms, and homes. The competitiveness of power generation with lower quality hydrothermal fluids, geopressured brines, hot dry rock, and magma ( the four types of geothermal energy) still depends on the technical advancements sought by DOE's Geothermal Energy Program.

  15. Monthly energy review June 1996

    SciTech Connect

    1996-06-01

    This report presents data on energy consumption, fossil fuels imports, supply and disposition, energy prices, electricity, nuclear energy electricity production, and international energy production and consumption.

  16. Alternative Energy Development and China's Energy Future

    SciTech Connect

    Zheng, Nina; Fridley, David

    2011-06-15

    In addition to promoting energy efficiency, China has actively pursued alternative energy development as a strategy to reduce its energy demand and carbon emissions. One area of particular focus has been to raise the share of alternative energy in China’s rapidly growing electricity generation with a 2020 target of 15% share of total primary energy. Over the last ten years, China has established several major renewable energy regulations along with programs and subsidies to encourage the growth of non-fossil alternative energy including solar, wind, nuclear, hydro, geothermal and biomass power as well as biofuels and coal alternatives. This study thus seeks to examine China’s alternative energy in terms of what has and will continue to drive alternative energy development in China as well as analyze in depth the growth potential and challenges facing each specific technology. This study found that despite recent policies enabling extraordinary capacity and investment growth, alternative energy technologies face constraints and barriers to growth. For relatively new technologies that have not achieved commercialization such as concentrated solar thermal, geothermal and biomass power, China faces technological limitations to expanding the scale of installed capacity. While some alternative technologies such as hydropower and coal alternatives have been slowed by uneven and often changing market and policy support, others such as wind and solar PV have encountered physical and institutional barriers to grid integration. Lastly, all alternative energy technologies face constraints in human resources and raw material resources including land and water, with some facing supply limitations in critical elements such as uranium for nuclear, neodymium for wind and rare earth metals for advanced solar PV. In light of China’s potential for and barriers to growth, the resource and energy requirement for alternative energy technologies were modeled and scenario analysis

  17. Landscaping for energy efficiency

    SciTech Connect

    1995-04-01

    This publication by the National Renewable Energy Laboratory addresses the use of landscaping for energy efficiency. The topics of the publication include minimizing energy expenses; landscaping for a cleaner environment; climate, site, and design considerations; planning landscape; and selecting and planting trees and shrubs. A source list for more information on landscaping for energy efficiency and a reading list are included.

  18. Zero Energy Use School.

    ERIC Educational Resources Information Center

    Nelson, Brian, Ed.; And Others

    The economic and physical realities of an energy shortage have caused many educators to consider alternative sources of energy when constructing their schools. This book contains studies and designs by fifth-year architecture students concerning the proposed construction of a zero energy-use elementary school in Albany, Oregon. "Zero energy use"…

  19. Campus Energy Modeling Platform

    SciTech Connect

    Sides, Scott; Kemper, Travis; Larsen, Ross; Graf, Peter

    2014-09-19

    NREL's Campus Energy Modeling project provides a suite of simulation tools for integrated, data driven energy modeling of commercial buildings and campuses using Simulink. The tools enable development of fully interconnected models for commercial campus energy infrastructure, including electrical distribution systems, district heating and cooling, onsite generation (both conventional and renewable), building loads, energy storage, and control systems.

  20. Saving Energy Dollars.

    ERIC Educational Resources Information Center

    Cray, Douglas W.

    1993-01-01

    The Comprehensive National Energy Policy Act of 1992 encourages energy-conservation measures and proposes matching federal energy-conservation funds with state programs to achieve energy conservation in public buildings. Presents a sampler of conservation projects in Massachusetts, Connecticut, Florida, and Minnesota. (MLF)

  1. The Carter Energy Plan

    ERIC Educational Resources Information Center

    Coan, Gene

    1977-01-01

    Plans for the implementation of a national energy policy are outlined. Proposed measures in the following areas are discussed: energy conservation; energy systems and rates; energy pricing and equity; coal, oil and gas production; nuclear and solar power; and industry structure and competition. Concerns of environmentalists are expressed. (AJ)

  2. Profiles in Energy.

    ERIC Educational Resources Information Center

    National Council for Resource Development, Washington, DC.

    In order to assist two-year college educators in increasing their participation in energy-related activities, this publication provides guidelines for planning energy projects and descriptions of model energy programs. The steps outlined for program planning include the assessment of area energy resources, the identification of local…

  3. Evaluating Energy Conversion Efficiency

    NASA Technical Reports Server (NTRS)

    Byvik, C. E.; Smith, B. T.; Buoncristiani, A. M.

    1983-01-01

    Devices that convert solar radiation directly into storable chemical or electrical energy, have characteristic energy absorption spectrum; specifically, each of these devices has energy threshold. The conversion efficiency of generalized system that emcompasses all threshold devices is analyzed, resulting in family of curves for devices of various threshold energies operating at different temperatures.

  4. Solar Energy: Heat Transfer.

    ERIC Educational Resources Information Center

    Knapp, Henry H., III

    This module on heat transfer is one of six in a series intended for use as supplements to currently available materials on solar energy and energy conservation. Together with the recommended texts and references (sources are identified), these modules provide an effective introduction to energy conservation and solar energy technologies. The…

  5. Solar Energy: Heat Storage.

    ERIC Educational Resources Information Center

    Knapp, Henry H., III

    This module on heat storage is one of six in a series intended for use as supplements to currently available materials on solar energy and energy conservation. Together with the recommended texts and references (sources are identified), these modules provide an effective introduction to energy conservation and solar energy technologies. The module…

  6. Solar Energy: Home Heating.

    ERIC Educational Resources Information Center

    Knapp, Henry H., III

    This module on home heating is one of six in a series intended for use as supplements to currently available materials on solar energy and energy conservation. Together with the recommended texts and references (sources are identified), these modules provide an effective introduction to energy conservation and solar energy technologies. The module…

  7. Energy and Rural Schooling.

    ERIC Educational Resources Information Center

    Stephan, Edward; And Others

    A number of disadvantages cripple school efforts to face current energy shortages. Most schools were built at a time when energy was inexpensive and abundant and their structural design gave little regard to energy efficiency. Coupled with poor maintenance programs, school facilities may waste as much as 25 to 50 percent of the energy used. As an…

  8. Energy Facts 1988.

    ERIC Educational Resources Information Center

    Energy Information Administration (DOE), Washington, DC.

    This booklet is a compilation of energy data providing a reference to a much broader range of domestic and international energy data. It is designed especially as a quick reference to major facts about energy. The data includes information for 1976 through 1988, except for international energy data, which is for 1977 through 1987. Graphs, charts,…

  9. Alternatives in solar energy

    NASA Technical Reports Server (NTRS)

    Schueler, D. G.

    1978-01-01

    Although solar energy has the potential of providing a significant source of clean and renewable energy for a variety of applications, it is expected to penetrate the nation's energy economy very slowly. The alternative solar energy technologies which employ direct collection and conversion of solar radiation as briefly described.

  10. Monthly energy review

    SciTech Connect

    1997-12-01

    This document presents an overview of the Energy Information Administration`s (EIA) recent monthly energy statistics. The statistics cover the major activities of U.S. production, consumption, trade, stocks, and prices for petroleum, natural gas, coal, electricity, and nuclear energy. Also included are international energy and thermal and metric conversion factors.

  11. Energy: Options and Issues.

    ERIC Educational Resources Information Center

    Walker, Harry O.

    This book is intended to provide basic information about energy. The first three chapters describe energy supply and demand, uses and sources, and common energy terms. The next two chapters explain environmental and biological effects of energy systems. Twelve chapters that follow outline past history and technological knowledge of the following…

  12. Energy Options for Man.

    ERIC Educational Resources Information Center

    Tratner, Karen Lee

    Produced for public interest, the Environmental Education Group has prepared this two-part review of the current state of energy utilization, the nature of the energy crisis, and approaches to energy production. The major section is a presentation of alternative sources of energy that are neglected, are of possible aid in the near future, or are…

  13. The Energy To Teach.

    ERIC Educational Resources Information Center

    Graves, Donald H.

    2002-01-01

    Learns from teachers themselves what gave and took away energy from their teaching experiences. Considers what gives teachers energy or takes it away and what is a waste of time. Outlines and discusses eight energy principles. Concludes that most individuals are energy-filled when they are learning themselves. (SG)

  14. Radiant energy collector

    DOEpatents

    Winston, Roland

    1977-01-11

    An electromagnetic energy collection device is provided which does not require a solar tracking capability. It includes an energy receiver positioned between two side walls which reflect substantially all incident energy received over a predetermined included angle directly onto the energy receiver.

  15. Energy Directory and Bibliography.

    ERIC Educational Resources Information Center

    Berman, Richard M.; Hunt, Irmgard

    This publication is written as a reference guide for persons interested in energy conservations, alternative energy sources, and energy conscious lifestyles. It consists of both a directory to organizations that can provide energy information and a bibliography of useful consumer-oriented publications. The directory includes leading private and…

  16. Energy 101: Electric Vehicles

    SciTech Connect

    2012-01-01

    This edition of Energy 101 highlights the benefits of electric vehicles, including improved fuel efficiency, reduced emissions, and lower maintenance costs. For more information on electric vehicles from the Office of Energy Efficiency and Renewable Energy, visit the Vehicle Technologies Program website: http://www1.eere.energy.gov/vehiclesandfuels/

  17. Home energy saver's handbook

    NASA Astrophysics Data System (ADS)

    Koga, N. N.

    1980-09-01

    Energy is described and how much energy a household consumes is discussed. The saving of energy is recommended and measures to save energy when operating hot water heaters, air conditioners, lighting systems refrigerators, freezers, stoves, microwave ovens, washing machines, clothes dryers, dishwashers, television sets, and portable appliances are summarized.

  18. Energy 101: Electric Vehicles

    ScienceCinema

    None

    2016-07-12

    This edition of Energy 101 highlights the benefits of electric vehicles, including improved fuel efficiency, reduced emissions, and lower maintenance costs. For more information on electric vehicles from the Office of Energy Efficiency and Renewable Energy, visit the Vehicle Technologies Program website: http://www1.eere.energy.gov/vehiclesandfuels/

  19. Home Energy Score

    SciTech Connect

    2011-12-16

    The Home Energy Score allows a homeowner to compare her or his home's energy consumption to that of other homes, similar to a vehicle's mile-per-gallon rating. A home energy assessor will collect energy information during a brief home walk-through and then score that home on a scale of 1 to 10.

  20. Energy 101: Energy Efficient Data Centers

    SciTech Connect

    2011-01-01

    Data centers provide mission-critical computing functions vital to the daily operation of top U.S. economic, scientific, and technological organizations. These data centers consume large amounts of energy to run and maintain their computer systems, servers, and associated high-performance components—up to 3% of all U.S. electricity powers data centers. And as more information comes online, data centers will consume even more energy. Data centers can become more energy efficient by incorporating features like power-saving "stand-by" modes, energy monitoring software, and efficient cooling systems instead of energy-intensive air conditioners. These and other efficiency improvements to data centers can produce significant energy savings, reduce the load on the electric grid, and help protect the nation by increasing the reliability of critical computer operations.

  1. Energy 101: Energy Efficient Data Centers

    ScienceCinema

    None

    2016-07-12

    Data centers provide mission-critical computing functions vital to the daily operation of top U.S. economic, scientific, and technological organizations. These data centers consume large amounts of energy to run and maintain their computer systems, servers, and associated high-performance components—up to 3% of all U.S. electricity powers data centers. And as more information comes online, data centers will consume even more energy. Data centers can become more energy efficient by incorporating features like power-saving "stand-by" modes, energy monitoring software, and efficient cooling systems instead of energy-intensive air conditioners. These and other efficiency improvements to data centers can produce significant energy savings, reduce the load on the electric grid, and help protect the nation by increasing the reliability of critical computer operations.

  2. National Energy Act statutes and solar energy

    SciTech Connect

    Howard, J.

    1980-02-01

    The National Energy Act of 1978 contains many provisions that will significantly affect solar technology commercialization and solar energy users. Four of the five statutes that comprise the National Energy Act deserve close attention. The National Energy Conservation Policy Act will promote residential solar installations. The Energy Tax Act will accelerate both residential and commercial solar system applications. The Public Utilities Regulatory Policies Act promotes efficient use of utility resources as well as decentralized power production. And, the Power Plan and Industrial Fuel Use Act places severe restrictions on future burning of petroleum and natural gas, which should lead some operators to build or convert to solar energy systems. Each of the preceding acts are considered in separate sections of this report. Federal regulations issued pursuant to the various provisions are also identified and discussed, and some of the problems with the provisions and regulations are noted.

  3. Energy Week presentations

    SciTech Connect

    2006-07-01

    Topics covered include: energy security; clean energy and low carbon; energy for growth and poverty reduction in Africa; financing of energy efficiency; SMEs for decentralised energy service provision; potential for biofuels in developing countries; clean energy and sustainable development; clean energy finance and private equity funds; power generation and low carbon technologies; beyond traditional finance; rehabilitation and emission control in thermal power plants; and carbon finance. The presentations are mainly in ppt (Power Point) or pdf (Acrobat) format. Some videos of the conference are also available on the website.

  4. China Energy Primer

    SciTech Connect

    Ni, Chun Chun

    2009-11-16

    Based on extensive analysis of the 'China Energy Databook Version 7' (October 2008) this Primer for China's Energy Industry draws a broad picture of China's energy industry with the two goals of helping users read and interpret the data presented in the 'China Energy Databook' and understand the historical evolution of China's energy inustry. Primer provides comprehensive historical reviews of China's energy industry including its supply and demand, exports and imports, investments, environment, and most importantly, its complicated pricing system, a key element in the analysis of China's energy sector.

  5. Renewable energy annual 1996

    SciTech Connect

    1997-03-01

    This report presents summary data on renewable energy consumption, the status of each of the primary renewable technologies, a profile of each of the associated industries, an analysis of topical issues related to renewable energy, and information on renewable energy projects worldwide. It is the second in a series of annual reports on renewable energy. The renewable energy resources included in the report are biomass (wood and ethanol); municipal solid waste, including waste-to-energy and landfill gas; geothermal; wind; and solar energy, including solar thermal and photovoltaic. The report also includes various appendices and a glossary.

  6. Annual Energy Review 2010

    SciTech Connect

    2011-10-01

    This twenty-ninth edition of the Annual Energy Review (AER) presents the U.S. Energy Information Administration’s (EIA) most comprehensive look at integrated energy statistics. The summary statistics on the Nation’s energy production, consumption, trade, stocks, and prices cover all major energy commodities and all energy-consuming sectors of the U.S. economy from 1949 through 2010. The AER is EIA’s historical record of energy statistics and, because the coverage spans six decades, the statistics in this report are well-suited to long-term trend analysis.

  7. Energy Tracking Software Platform

    SciTech Connect

    Ryan Davis; Nathan Bird; Rebecca Birx; Hal Knowles

    2011-04-04

    Acceleration has created an interactive energy tracking and visualization platform that supports decreasing electric, water, and gas usage. Homeowners have access to tools that allow them to gauge their use and track progress toward a smaller energy footprint. Real estate agents have access to consumption data, allowing for sharing a comparison with potential home buyers. Home builders have the opportunity to compare their neighborhood's energy efficiency with competitors. Home energy raters have a tool for gauging the progress of their clients after efficiency changes. And, social groups are able to help encourage members to reduce their energy bills and help their environment. EnergyIT.com is the business umbrella for all energy tracking solutions and is designed to provide information about our energy tracking software and promote sales. CompareAndConserve.com (Gainesville-Green.com) helps homeowners conserve energy through education and competition. ToolsForTenants.com helps renters factor energy usage into their housing decisions.

  8. Great Lakes Energy Institute

    SciTech Connect

    Alexander, J. Iwan

    2012-11-18

    The vision of the Great Lakes Energy Institute is to enable the transition to advanced, sustainable energy generation, storage, distribution and utilization through coordinated research, development, and education. The Institute will place emphasis on translating leading edge research into next generation energy technology. The Institute’s research thrusts focus on coordinated research in decentralized power generation devices (e.g. fuel cells, wind turbines, solar photovoltaic devices), management of electrical power transmission and distribution, energy storage, and energy efficiency.

  9. Solar energy emplacement developer

    NASA Technical Reports Server (NTRS)

    Mortensen, Michael; Sauls, Bob

    1991-01-01

    A preliminary design was developed for a Lunar Power System (LPS) composed of photovoltaic arrays and microwave reflectors fabricated from lunar materials. The LPS will collect solar energy on the surface of the Moon, transform it into microwave energy, and beam it back to Earth where it will be converted into usable energy. The Solar Energy Emplacement Developer (SEED) proposed will use a similar sort of solar energy collection and dispersement to power the systems that will construct the LPS.

  10. Programs in Renewable Energy

    SciTech Connect

    Not Available

    1990-01-01

    Our nation faces significant challenges as we enter the 1990s: securing a reliable supply of competitively priced energy, improving the quality of our environment, and increasing our share of foreign markets for goods and services. The US Department of Energy's (DOE) Programs in Renewable Energy are working toward meeting these challenges by developing the technologies that make use of our nation's largest energy resource: renewable energy. The sunlight, wind biomass, flowing water, ocean energy, and geothermal energy that make up the renewable energy resource can be found throughout our nation. These resources can provide all the forms of energy our nation needs: liquid fuels, electricity, and heating and cooling. Renewable energy meets about 10% of our need for these forms of energy today, yet the potential contribution is many times greater. DOE's Programs in Renewable Energy are working side-by-side with American industry to develop the technologies that convert renewable energy resources into practical, cost-competitive energy. After a decade of progress in research, several of these technologies are poised to make large contributions during the 1990s and beyond. This booklet provides an overview of the renewable energy programs and their plans for FY 1990. Sources of additional information are listed at the back of the booklet. 48 figs., 4 tabs.

  11. Energy Tracking Diagrams

    NASA Astrophysics Data System (ADS)

    Scherr, Rachel E.; Harrer, Benedikt W.; Close, Hunter G.; Daane, Abigail R.; DeWater, Lezlie S.; Robertson, Amy D.; Seeley, Lane; Vokos, Stamatis

    2016-02-01

    Energy is a crosscutting concept in science and features prominently in national science education documents. In the Next Generation Science Standards, the primary conceptual learning goal is for learners to conserve energy as they track the transfers and transformations of energy within, into, or out of the system of interest in complex physical processes. As part of tracking energy transfers among objects, learners should (i) distinguish energy from matter, including recognizing that energy flow does not uniformly align with the movement of matter, and should (ii) identify specific mechanisms by which energy is transferred among objects, such as mechanical work and thermal conduction. As part of tracking energy transformations within objects, learners should (iii) associate specific forms with specific models and indicators (e.g., kinetic energy with speed and/or coordinated motion of molecules, thermal energy with random molecular motion and/or temperature) and (iv) identify specific mechanisms by which energy is converted from one form to another, such as incandescence and metabolism. Eventually, we may hope for learners to be able to optimize systems to maximize some energy transfers and transformations and minimize others, subject to constraints based in both imputed mechanism (e.g., objects must have motion energy in order for gravitational energy to change) and the second law of thermodynamics (e.g., heating is irreversible). We hypothesize that a subsequent goal of energy learning—innovating to meet socially relevant needs—depends crucially on the extent to which these goals have been met.

  12. 75 FR 70214 - Renewable Energy and Energy Efficiency Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-17

    ... International Trade Administration Renewable Energy and Energy Efficiency Advisory Committee AGENCY... Renewable Energy and Energy Efficiency Advisory Committee (RE&EEAC) will hold its inaugural meeting to..., Office of Energy and Environmental Technologies Industries (OEEI), International Trade Administration,...

  13. 78 FR 48855 - Renewable Energy and Energy Efficiency Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-12

    ...; ] DEPARTMENT OF COMMERCE International Trade Administration Renewable Energy and Energy Efficiency Advisory... Meeting. SUMMARY: The Renewable Energy and Energy Efficiency Advisory Committee (RE&EEAC) will hold a...: Ryan Mulholland, Office of Energy and Environmental Industries (OEEI), International...

  14. NANA Strategic Energy Plan & Energy Options Analysis

    SciTech Connect

    Jay Hermanson; Brian Yanity

    2008-12-31

    NANA Strategic Energy Plan summary NRC, as an Alaska Native Corporation, has committed to addressing the energy needs for its shareholders. The project framework calls for implicit involvement of the IRA Councils in the Steering Committee. Tribal Members, from the NRC to individual communities, will be involved in development of the NANA Energy Plan. NRC, as the lead tribal entity, will serve as the project director of the proposed effort. The NRC team has communicated with various governmental and policy stakeholders via meetings and discussions, including Denali Commission, Alaska Energy Authority, and other governmental stakeholders. Work sessions have been initiated with the Alaska Village Electric Cooperative, the NW Arctic Borough, and Kotzebue Electric Association. The NRC Strategic Energy Plan (SEP) Steering committee met monthly through April and May and weekly starting in June 2008 in preparation of the energy summit that was held from July 29-31, 2008. During preparations for the energy summit and afterwards, there was follow through and development of project concepts for consideration. The NANA regional energy summit was held from July 29-31, 2008, and brought together people from all communities of the Northwest Arctic Borough. The effort was planned in conjunction with the Alaska Energy Authority’s state-wide energy planning efforts. Over $80,000 in cash contributions was collected from various donors to assist with travel from communities and to develop the summit project. Available funding resources have been identified and requirements reviewed, including the Denali Commission, U.S. Dept. of Agriculture, and the Alaska Energy Authority. A component of the overall plan will be a discussion of energy funding and financing. There are current project concepts submitted, or are ready for submittal, in the region for the following areas: • Wind-diesel in Deering, Buckland, Noorik, and Kiana areas; potential development around Red Dog mine.

  15. Monthly energy review, January 1997

    SciTech Connect

    1997-01-01

    This is an overview of the January energy statistics by the Energy Information Administration. The contents of the report include an energy overview, US energy production, energy consumption, trade stocks and prices for petroleum, natural gas, oil and gas resource development, coal, electricity, nuclear energy, energy prices, and international energy. 47 figs., 71 tabs.

  16. Energy for America's Third Century

    ERIC Educational Resources Information Center

    MOSAIC, 1974

    1974-01-01

    Six articles concerned with energy use, energy research and sources of energy are included in this issue. Articles are titled (1) Energy Systems; (2) Energy-Related Research; (3) Solar Energy; (4) Geothermal Energy; (5) Coal; and (6) Utilization of Energy. (RH)

  17. Prospects for Sustainable Energy

    NASA Astrophysics Data System (ADS)

    Cassedy, Edward S., Jr.

    2000-04-01

    Fossil fuels are a finite resource, and their continued use as the world's dominant energy supply is damaging the environment. Future use of alternative methods of energy supply is inescapable. This book offers a critical assessment of all possible sustainable energy technologies and energy storage. Coverage explores the historical origins, technical features, marketability, and environmental impacts of the complete range of sustainable energy technologies: solar, biomass, wind, hydropower, geothermal power, ocean-energy sources, solar-derived hydrogen fuel, and energy storage. The aim is to inform policy analysts and decision makers of the options available for sustainable energy production. This accessible volume will be a valuable resource for a broad group of academics and researchers with a wide range of backgrounds and scientific training. It will also be an ideal supplementary next for advanced courses in environmental studies, energy economics and policy, and engineering.

  18. Future American energy policy

    SciTech Connect

    Crist, M.S.; Laffer, A.B.

    1982-01-01

    People from businesses, public life, public advocacy groups, and experts on international energy met in February 1980 to explore the complex issues of energy policy at a conference entitled Energy Future: Policies and Consequences. The book begins with Crist's overview of current options. David Stockman then examines damaging energy myths and their effects in producing misguided energy policies. Other authors explore the social implications of energy policy, the failure of oil-company management and government to keep energy prices in line with costs, the economic implications of domestic energy policy, international attitudes toward US policy, and the implications of alternative energy sources and conservation. Laffer describes how American presidential economic policies differ from public perceptions. The book concludes with the hope of achieving a future balance of environmental concerns and increased production.

  19. Annual Energy Review 2007

    SciTech Connect

    Seiferlein, Katherine E.

    2008-06-01

    The Annual Energy Review (AER) is the Energy Information Administration's (EIA) primary report of annual historical energy statistics. For many series, data begin with the year 1949. Included are data on total energy production, consumption, and trade; overviews of petroleum, natural gas, coal, electricity, nuclear energy, renewable energy, international energy, as well as financial and environment indicators; and data unit conversion tables. Publication of this report is required under Public Law 95–91 (Department of Energy Organization Act), Section 205(c), and is in keeping with responsibilities given to the EIA under Section 205(a)(2), which states: “The Administrator shall be responsible for carrying out a central, comprehensive, and unified energy data and information program which will collect, evaluate, assemble, analyze, and disseminate data and information....”

  20. Nonimaging radiant energy device

    DOEpatents

    Winston, Roland; Ning, Xiaohui

    1996-01-01

    A nonimaging radiant energy device may include a hyperbolically shaped reflective element with a radiant energy inlet and a radiant energy outlet. A convex lens is provided at the radiant energy inlet and a concave lens is provided at the radiant energy outlet. Due to the provision of the lenses and the shape of the walls of the reflective element, the radiant energy incident at the radiant energy inlet within a predetermined angle of acceptance is emitted from the radiant energy outlet exclusively within an acute exit angle. In another embodiment, the radiant energy device may include two interconnected hyperbolically shaped reflective elements with a respective convex lens being provided at each aperture of the device.

  1. Nonimaging radiant energy device

    DOEpatents

    Winston, Roland; Ning, Xiaohui

    1993-01-01

    A nonimaging radiant energy device may include a hyperbolically shaped reflective element with a radiant energy inlet and a radiant energy outlet. A convex lens is provided at the radiant energy inlet and a concave lens is provided at the radiant energy outlet. Due to the provision of the lenses and the shape of the walls of the reflective element, the radiant energy incident at the radiant energy inlet within a predetermined angle of acceptance is emitted from the radiant energy outlet exclusively within an acute exit angle. In another embodiment, the radiant energy device may include two interconnected hyperbolically shaped reflective elements with a respective convex lens being provided at each aperture of the device.

  2. Making energy mortgages work

    SciTech Connect

    Luboff, J.A.

    1995-05-01

    At a time when many energy efficiency projects face an uncertain future, home energy ratings and energy mortgages are receiving more attention than ever. Will enthusiasm in the industry and new programs from conventional lenders and the federal government finally open up the market? This article describes the energy morgage marketplace, how energy mortages work, and what the future holds. Topics include the following: Who`s who and what`s what in the EM marketplace; initial Freddie Mac and Fannie Mae guidelines; past and present home energy rating system; how do you score a house; how an energy mortage works; energy improvement loans; sample rating certificate; fixing the system; Colorado`s conventional market approach; US DOE`s pilot group; energy mortages set to take off.

  3. Energy accounting of alternative energy sources

    NASA Astrophysics Data System (ADS)

    Roberts, F.

    1980-02-01

    An energy accounting study was performed in the United Kingdom of five alternative energy resource systems - solar, geothermal, wind, wave and tidal power. The paper gives the data sources, the assumptions, an outline of the procedure, results and some general comments for each case. A detailed comparison with regard to likely energy ratios is not possible; however, a value of about 10:1 is seen as reasonable for the future. Based on such an energy ratio the likely factor saving for wind, wave and tidal energy systems is around 33:1. In the case of solar and geothermal energy it could vary from 6:1 through 23:1, depending upon system design, local conditions, etc. Energy pay-back times are short for all the systems, the longest being about four-and-a-half years. Finally, it is noted that our primary non-renewable fuels could be considerably conserved by using them to operate renewable energy resources even if economic analysis shows that at the present time such a policy is hardly justified.

  4. Energy Conservation. CORD Energy Technology Series.

    ERIC Educational Resources Information Center

    Center for Occupational Research and Development, Inc., Waco, TX.

    This course in energy conservation is one of 16 courses in the Energy Conservation-and-Use Technology curriculum. Intended for use in two-year postsecondary technical institutions to prepare technicians for employment, the courses are also useful in industry for updating employees in company-sponsored training programs. Comprised of seven modules,…

  5. Science Activities in Energy: Wind Energy.

    ERIC Educational Resources Information Center

    Oak Ridge Associated Universities, TN.

    Included in this science activities energy package are 12 activities related to wind energy for elementary students. Each activity is outlined on a single card and is introduced by a question. Topics include: (1) At what time of day is there enough wind to make electricity where you live?; (2) Where is the windiest spot on your schoolground?; and…

  6. Radiant energy to electric energy converter

    NASA Technical Reports Server (NTRS)

    Sher, Arden (Inventor)

    1980-01-01

    Radiant energy is converted into electric energy by irradiating a capacitor including an ionic dielectric. The dielectric is a sintered crystal superionic conductor, e.g., lanthanum trifluoride, lanthanum trichloride, or silver bromide, so that a multiplicity of crystallites exist between electrodes of the capacitor. The radiant energy cyclically irradiates the dielectric so that the dielectric exhibits a cyclic photocapacitive like effect. Adjacent crystallites have abutting surfaces that enable the crystallites to effectively form a multiplicity of series capacitor elements between the electrodes. Each of the capacitor elements has a dipole layer only on or near its surface. The capacitor is initially charged to a voltage just below the dielectric breakdown voltage by connecting it across a DC source causing a current to flow through a charging resistor to the dielectric. The device can be utilized as a radiant energy detector or as a solar energy cell.

  7. Monthly energy review, August 1993

    SciTech Connect

    Not Available

    1993-08-26

    This publication presents information for the month of August, 1993 on the following: Energy overview; energy consumption; petroleum; natural gas; oil and gas resource development; coal; electricity; nuclear energy; energy prices, and international energy.

  8. Alaska's renewable energy potential.

    SciTech Connect

    Not Available

    2009-02-01

    This paper delivers a brief survey of renewable energy technologies applicable to Alaska's climate, latitude, geography, and geology. We first identify Alaska's natural renewable energy resources and which renewable energy technologies would be most productive. e survey the current state of renewable energy technologies and research efforts within the U.S. and, where appropriate, internationally. We also present information on the current state of Alaska's renewable energy assets, incentives, and commercial enterprises. Finally, we escribe places where research efforts at Sandia National Laboratories could assist the state of Alaska with its renewable energy technology investment efforts.

  9. Wind energy bibliography

    SciTech Connect

    1995-05-01

    This bibliography is designed to help the reader search for information on wind energy. The bibliography is intended to help several audiences, including engineers and scientists who may be unfamiliar with a particular aspect of wind energy, university researchers who are interested in this field, manufacturers who want to learn more about specific wind topics, and librarians who provide information to their clients. Topics covered range from the history of wind energy use to advanced wind turbine design. References for wind energy economics, the wind energy resource, and environmental and institutional issues related to wind energy are also included.

  10. Home Energy Assessments

    ScienceCinema

    Dispenza, Jason

    2016-07-12

    A home energy assessment, also known as a home energy audit, is the first step to assess how much energy your home consumes and to evaluate what measures you can take to make your home more energy efficient. An assessment will show you problems that may, when corrected, save you significant amounts of money over time. This video shows some of the ways that a contractor may test your home during an assessment, and helps you understand how an assessment can help you move toward energy savings. Find out more at: http://www.energysavers.gov/your_home/energy_audits/index.cfm/mytopic=11160

  11. International energy annual 1996

    SciTech Connect

    1998-02-01

    The International Energy Annual presents an overview of key international energy trends for production, consumption, imports, and exports of primary energy commodities in over 220 countries, dependencies, and areas of special sovereignty. Also included are population and gross domestic product data, as well as prices for crude oil and petroleum products in selected countries. Renewable energy reported in the International Energy Annual includes hydroelectric power, geothermal, solar, and wind electric power, biofuels energy for the US, and biofuels electric power for Brazil. New in the 1996 edition are estimates of carbon dioxide emissions from the consumption of petroleum and coal, and the consumption and flaring of natural gas. 72 tabs.

  12. Home Energy Assessments

    SciTech Connect

    Dispenza, Jason

    2010-01-01

    A home energy assessment, also known as a home energy audit, is the first step to assess how much energy your home consumes and to evaluate what measures you can take to make your home more energy efficient. An assessment will show you problems that may, when corrected, save you significant amounts of money over time. This video shows some of the ways that a contractor may test your home during an assessment, and helps you understand how an assessment can help you move toward energy savings. Find out more at: http://www.energysavers.gov/your_home/energy_audits/index.cfm/mytopic=11160

  13. Energy and resource consumption

    NASA Technical Reports Server (NTRS)

    1973-01-01

    The present and projected energy requirements for the United States are discussed. The energy consumption and demand sectors are divided into the categories: residential and commercial, transportation, and industrial and electrical generation (utilities). All sectors except electrical generation use varying amounts of fossile fuel resources for non-energy purposes. The highest percentage of non-energy use by sector is industrial with 71.3 percent. The household and commercial sector uses 28.4 percent, and transportation about 0.3 percent. Graphs are developed to project fossil fuel demands for non-energy purposes and the perdentage of the total fossil fuel used for non-energy needs.

  14. The Global Energy Challenge

    ScienceCinema

    Crabtree, George

    2016-07-12

    The expected doubling of global energy demand by 2050 challenges our traditional patterns of energy production, distribution and use.   The continued use of fossil fuels raises concerns about supply, security, environment and climate.  New routes are needed for the efficient conversion of energy from chemical fuel, sunlight, and heat to electricity or hydrogen as an energy carrier and finally to end uses like transportation, lighting, and heating. Opportunities for efficient new energy conversion routes based on nanoscale materials will be presented, with emphasis on the sustainable energy technologies they enable.

  15. Energy Education Incentives: Evaluating the Impact of Consumer Energy Kits

    ERIC Educational Resources Information Center

    Kirby, Sarah D.; Guin, Autumn; Langham, Laura

    2015-01-01

    Measuring the energy and environmental impact of residential energy education efforts is difficult. The E-Conservation residential energy management program uses consumer energy kits to document the impact of energy-efficient improvements. The consumer energy kit provides an incentive for individuals attending energy education workshop, helps…

  16. Energy signature analysis: Radar for energy managers

    SciTech Connect

    Lambert, L.

    1998-07-01

    Energy Signature Analysis (ESA) acts as a noise filter, to enhance usefulness of energy data. It provides vital feedback on operating and maintenance (O{ampersand}M) consistency and strategies, trends, and on conservation changes to facilities and equipment. Energy and temperatures characterize building performance, Energy use drivers fall in one of two groups: (1) weather and inside temperature, or (2) building characteristics, occupancy, and O and M practices. ESA weather-normalizes with delta T, and uses optimal smoothing to minimize weather, occupancy, and thermostat-driven scatter in energy use. The remaining variability arises from causes of great interest--changes in building characteristics, occupancy patterns, and O and M practices. Energy use rate is plotted versus coincident delta T, for sequenced typical weeks. When nothing but weather changes, consistently managed buildings show low scatter; r{sup 2} for regular occupancy is often 0.96 or better. Efficiency requires consistency; energy use should only change with weather and thermostat settings. Inconsistent management or equipment faults cause scatter, outliers, or an uptrend to alert management. Improved consistence reduces scatter. Worthwhile retrofits, HVAC tuning, and improved management strategies lower the curve. Important changes show merit in a week. High scatter cripples purely statistical uses of building energy data. For ESA, outliers are chances to find inconsistency and behaviors to avoid (high outliers) or foster (low outliers). Area-normalized ESA permits comparing facilities with different size or weather. Model output for new buildings, recast in ESA format, can help track building commissioning or give modelers feedback. Example ESAs use hourly total energy, outside and sampled inside temperatures. Problems found are investigated using hourly HVAC and baseload data. Baseload and HVAC loadshapes show peak-shaving, shut-down and tuning opportunities. New weekly data points show results

  17. Special Report: Energy

    ERIC Educational Resources Information Center

    Cuscaden, Rob

    1976-01-01

    Presently available design techniques, technologies, and management practices can significantly reduce the energy requirements of new buildings. A two-part section discusses solutions to the energy problem in the commercial, institutional, and industrial fields. (Author/MLF)

  18. Energy of an Astronaut

    NASA Video Gallery

    Where does the energy of a space explorer come from? Find out about caloric intake, energy needs, and the metabolism inside the human space explorer's body by testing for starch with flour tortilla...

  19. Foundry energy conservation workbook

    SciTech Connect

    Not Available

    1990-01-01

    The foundry industry is a significant user of energy, and therefore, a natural candidate for efforts to save energy and improve efficiency by both governmental agencies and technical/trade associations. These efforts are designed to both improve the national energy position and improve the industry's efficiency and profitability. Increased energy cost and the reduced availability of fossil fuels at certain times have provided the incentive to curb waste and to utilize purchased energy wisely. Energy costs now approach and sometimes exceed 10% of the sales dollar of many foundries. Although energy use by foundries has gradually decreased on a per/ton basis in recent years, the foundry industry must continue to find ways to utilize energy more efficiently. This workbook provides ways to achieve this goal.

  20. Manage Energy with Computers.

    ERIC Educational Resources Information Center

    American School and University, 1982

    1982-01-01

    Computerized energy management at Drew University (New Jersey) is accomplished by direct digital control in which microprocessor controllers control, monitor, and carry out energy management functions at the equipment level. (Author/MLF)

  1. Energy for Planet Earth.

    ERIC Educational Resources Information Center

    Davis, Ged R.

    1990-01-01

    Examined is the world society's ability to meet energy needs without destroying the earth. Supply and demand issues are examined. International per capita energy use is compared. Historical trends are described. (CW)

  2. Energy design for architects

    SciTech Connect

    Shaw, A.

    1989-01-01

    This book contains techniques for energy efficiency in architectural design. Many aspects are covered including: cost; comfort and health; energy use; the design process; and analytical techniques. 202 figs. (JF)

  3. Teaching about Energy.

    ERIC Educational Resources Information Center

    Schlene, Vickie J.

    1992-01-01

    Provides a partial listing of documents from the ERIC database dealing with energy. Includes information on natural resources, curriculum planning, and energy development. Suggests available educational materials including curriculum plans from Oregon, Maine, and federal agencies. (DK)

  4. Air transportation energy efficiency

    NASA Technical Reports Server (NTRS)

    Williams, L. J.

    1977-01-01

    The energy efficiency of air transportation, results of the recently completed RECAT studies on improvement alternatives, and the NASA Aircraft Energy Efficiency Research Program to develop the technology for significant improvements in future aircraft were reviewed.

  5. The energy quandary

    SciTech Connect

    LePori, W.A. )

    1991-03-01

    As the war in the Middle East draws attention to energy needs, agricultural engineers will have the opportunity to contribute to a rational energy use policy. Even before the war, changes were occurring that pointed to the need for reviewing energy use in agriculture. A new consciousness of environmental problems is arising in the US. Many changes such as recycling, new pesticide regulations, more stringent air and water quality standards, new food quality standards, and others will directly impact energy use within the food and fiber producing industries. Energy issues should be addressed simultaneously with environmental issues. In the past, agricultural engineers have responded and provided significant contributions to help assure agriculture's energy needs. Their participation and input is again vital to assure availability of adequate energy for agriculture and development of energy resources from agriculture.

  6. The goldstone energy project

    NASA Technical Reports Server (NTRS)

    Bartos, K. P.

    1978-01-01

    The Golstone Energy Project was established in 1974 to investigate ways in which the Goldstone Deep Space Complex in California could be made partly or completely energy-sufficient, especially through the use of solar- and wind-derived energy resources. Ways in which energy could be conserved at the Complex were also studied. Findings included data on both wind and solar energy. Obstacles to demonstrating energy self-sufficiency are: (1) operation and maintenance costs of solar energy systems are estimated to be much higher than conventional energy systems, (2) initial capital costs of present-day technology solar collectors are high and are compounded by low collector efficiency, and (3) no significant market force exists to create the necessary industry to reduce costs through mass production and broad open-market competition.

  7. Energy Research (Letter)

    SciTech Connect

    Runci, Paul J.; Clarke, Leon E.; Dooley, James J.

    2006-04-03

    This paper analyzes long-term trends in energy R&D investment in the industrialized world using data gathered by the International Energy Agency. While energy R&D investment declined sharply and steadily from 1980 to the mid-1990s, investment then stabilized and has remained essentially flat in the ensuing years. This development raises important questions about future energy R&D needs, particularly in the light of growing concerns about global climate change. While energy R&D investment increases may be necessary to respond effectively to climate change, the authors encourage policy makers to consider important distinctions between the nature of the this problem and the energy crises of the 1970s that initially spurred the growth of the energy R&D enterprise. Key differences in the contemporary environment may necessitate modifications to public sector energy R&D investment strategies.

  8. Energy information directory 1998

    SciTech Connect

    1998-11-01

    The National Energy Information Center (NEIC), as part of its mission, provides energy information and referral assistance to Federal, State, and local governments, the academic community, business and industrial organizations, and the general public. The two principal functions related to this task are: (1) operating a general access telephone line, and (2) responding to energy-related correspondence addressed to the Energy Information Administration (EIA). The Energy Information Directory was developed to assist the NEIC staff, as well as other Department of Energy (DOE) staff, in directing inquiries to the proper offices within DOE, other Federal agencies, or energy-related trade associations. The Directory lists most Government offices and trade associations that are involved in energy matters.

  9. Energy information directory 1994

    SciTech Connect

    Not Available

    1994-03-28

    The National Energy Information Center (NEIC), as part of its mission, provides energy information and referral assistance to Federal, State, and local governments, the academic community, business and industrial organizations, and the general public. The two principal functions related to this task are (1) operating a general access telephone line, and (2) responding to energy-related correspondence addressed to the Energy Information Administration (EIA). The Energy Information Directory was developed to assist the NEIC staff, as well as other Department of Energy (DOE) staff, in directing inquiries to the proper offices within DOE, other Federal agencies, or energy-related trade associations. The Directory is a list of most Government offices and trade associations that are involved in energy matters. It does not include those DOE offices which do not deal with the public or public information.

  10. Tapping The Sun's Energy

    ERIC Educational Resources Information Center

    Lee, David G.

    1974-01-01

    Describes several successful attempts to utilize solar energy for heating and providing electrical energy for homes. Indicates that more research and development are needed, especially in the area of large scale usage. (SLH)

  11. NASA and energy

    NASA Technical Reports Server (NTRS)

    1974-01-01

    NASA technology contributions to create energy sources include direct solar heating and cooling systems, wind generation of electricity, solar thermal energy turbine drives, solar cells, and techniques for locating, producing, and collecting organic materials for conversion into fuel.

  12. Industrial energy conservation technology

    SciTech Connect

    Schmidt, P.S.; Williams, M.A.

    1980-01-01

    A separate abstract was prepared for each of the 60 papers included in this volume, all of which will appear in Energy Research Abstracts (ERA); 21 were selected for Energy Abstracts for Policy Analysis (EAPA). (MCW)

  13. Industrial Energy Conservation Technology

    SciTech Connect

    Not Available

    1980-01-01

    A separate abstract was prepared for each of the 55 papers presented in this volume, all of which will appear in Energy Research Abstracts (ERA); 18 were selected for Energy Abstracts for Policy Analysis (EAPA). (MCW)

  14. Hybrid community energy systems.

    SciTech Connect

    Jody, B. J.; Daniels, E. J.; Karvelas, D. E.; Energy Systems

    2000-01-01

    The availability of efficient, economical, and reliable energy supplies can help attract industry and commercial businesses to a municipality or a region. Efficient use of energy can also improve the air quality and reduce pollution. Therefore, municipalities should explore and encourage the development and implementation of efficient energy systems. Integrated hybrid energy systems can be designed to meet the total energy requirements of large and small communities. These systems can yield significant energy and cost savings when compared with independent systems serving individual units or when compared with the conventional practice of buying power from a utility and producing thermal energy on-site. To maximize energy and cost savings, the design engineer should look beyond the conventional when designing such systems.

  15. GeoEnergy technology

    SciTech Connect

    1980-12-31

    The goal of the GeoEnergy Technology Program is to improve the understanding and efficiency of energy extraction and conversion from geologic resources, hence maintaining domestic production capability of fossil energy resources and expanding the usage of geothermal energy. The GeoEnergy Technology Program conducts projects for the Department of Energy in four resource areas--coal, oil and gas, synthetic fuels and geothermal energy. These projects, which are conducted collaboratively with private industry and DOE`s Energy Technology Centers, draw heavily on expertise derived from the nuclear weapons engineering capabilities of Sandia. The primary technologies utilized in the program are instrumentation development and application, geotechnical engineering, drilling and well completions, and chemical and physical process research. Studies in all four resource areas are described.

  16. Annual Energy Review 1999

    SciTech Connect

    Seiferlein, Katherine E.

    2000-07-01

    A generation ago the Ford Foundation convened a group of experts to explore and assess the Nation’s energy future, and published their conclusions in A Time To Choose: America’s Energy Future (Cambridge, MA: Ballinger, 1974). The Energy Policy Project developed scenarios of U.S. potential energy use in 1985 and 2000. Now, with 1985 well behind us and 2000 nearly on the record books, it may be of interest to take a look back to see what actually happened and consider what it means for our future. The study group sketched three primary scenarios with differing assumptions about the growth of energy use. The Historical Growth scenario assumed that U.S. energy consumption would continue to expand by 3.4 percent per year, the average rate from 1950 to 1970. This scenario assumed no intentional efforts to change the pattern of consumption, only efforts to encourage development of our energy supply. The Technical Fix scenario anticipated a “conscious national effort to use energy more efficiently through engineering know-how." The Zero Energy Growth scenario, while not clamping down on the economy or calling for austerity, incorporated the Technical Fix efficiencies plus additional efficiencies. This third path anticipated that economic growth would depend less on energy-intensive industries and more on those that require less energy, i.e., the service sector. In 2000, total energy consumption was projected to be 187 quadrillion British thermal units (Btu) in the Historical Growth case, 124 quadrillion Btu in the Technical Fix case, and 100 quadrillion Btu in the Zero Energy Growth case. The Annual Energy Review 1999 reports a preliminary total consumption for 1999 of 97 quadrillion Btu (see Table 1.1), and the Energy Information Administration’s Short-Term Energy Outlook (April 2000) forecasts total energy consumption of 98 quadrillion Btu in 2000. What energy consumption path did the United States actually travel to get from 1974, when the scenarios were drawn

  17. Energy information sheets

    SciTech Connect

    1995-07-01

    The National Energy Information Center (NEIC), as part of its mission, provides energy information and referral assistance to Federal, State, and local governments, the academic community, business and industrial organizations, and the public. The Energy Information Sheets was developed to provide general information on various aspects of fuel production, prices, consumption, and capability. Additional information on related subject matter can be found in other Energy Information Administration (EIA) publications as referenced at the end of each sheet.

  18. Solar energy collection system

    NASA Technical Reports Server (NTRS)

    Selcuk, M. K. (Inventor)

    1977-01-01

    An improved solar energy collection system, having enhanced energy collection and conversion capabilities, is delineated. The system is characterized by a plurality of receivers suspended above a heliostat field comprising a multiplicity of reflector surfaces, each being adapted to direct a concentrated beam of solar energy to illuminate a target surface for a given receiver. A magnitude of efficiency, suitable for effectively competing with systems employed in collecting and converting energy extracted from fossil fuels, is indicated.

  19. Diversification of energy sources

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The concept of energy source diversification was introduced as a substitution conservation action. The current status and philosophy behind a diversification program is presented in the context of a national energy policy. Advantages, disadvantages (constraints), and methods of implementation for diversification are discussed. The energy source systems for diversification are listed and an example impact assessment is outlined which deals with the water requirements of the specific energy systems.

  20. Energy industries abroad

    NASA Astrophysics Data System (ADS)

    1981-09-01

    The relationships between foreign governments and energy industries in many of the world's most important energy producing and consuming nations are examined. The history of hydrocarbon exploration and production is traced and the concessionary and other contractual arrangements entered into by foreign governments and international oil companies are reviewed. Petroleum legislation that was enacted, how government institutions gradually assumed more responsibility for energy matters, and how the former concessionaires adapted to accommodate this increased government participation in the energy sector is described.

  1. Annual Energy Outlook

    EIA Publications

    2016-01-01

    Projections in the Annual Energy Outlook 2016 (AEO2016) focus on the factors expected to shape U.S. energy markets through 2040. The projections provide a basis for examination and discussion of energy market trends and serve as a starting point for analysis of potential changes in U.S. energy policies, rules, and regulations, as well as the potential role of advanced technologies.

  2. Energy storage apparatus

    NASA Technical Reports Server (NTRS)

    Studer, P. A.; Evans, H. E. (Inventor)

    1978-01-01

    A high efficiency, flywheel type energy storage device which comprises an electronically commutated d.c. motor/generator unit having a massive flywheel rotor magnetically suspended around a ring shaped stator is presented. During periods of low energy demand, the storage devices were operated as a motor, and the flywheel motor was brought up to operating speed. Energy was drawn from the device functioning as a generator as the flywheel rotor rotated during high energy demand periods.

  3. Energy in history

    SciTech Connect

    Purs, J.

    1984-01-01

    This book presents the papers given at a symposium on the development of energy technologies in Czechoslovakia during the Industrial Revolution. Topics considered at the symposium included steam drive in the epoch of the Industrial Revolution, the energy crisis in the milling industry of late feudalism, the energy base of the food industry during the industrial and scientific revolution, power engineering in agriculture, and new energy in the transportation sector during the automobile revolution.

  4. Learning about saving energy

    SciTech Connect

    1995-02-01

    This fact sheet for use in primary and junior high school classes describes what energy is, how people use energy, and how energy can be conserved. This last section lists ways to save energy in heating and cooling, electric appliances, automobiles, and in manufacturing. A list of activities are suggested and resources for further information, both groups and books, are listed. A glossary is also included.

  5. National hydrogen energy roadmap

    SciTech Connect

    None, None

    2002-11-01

    This report was unveiled by Energy Secretary Spencer Abraham in November 2002 and provides a blueprint for the coordinated, long-term, public and private efforts required for hydrogen energy development. Based on the results of the government-industry National Hydrogen Energy Roadmap Workshop, held in Washington, DC on April 2-3, 2002, it displays the development of a roadmap for America's clean energy future and outlines the key barriers and needs to achieve the hydrogen vision goals defined in

  6. Energy efficient building design

    SciTech Connect

    Not Available

    1992-03-01

    The fundamental concepts of the building design process, energy codes and standards, and energy budgets are introduced. These tools were combined into Energy Design Guidelines and design contract requirements. The Guidelines were repackaged for a national audience and a videotape for selling the concept to government executives. An effort to test transfer of the Guidelines to outside agencies is described.

  7. Energy recovery injectors

    NASA Astrophysics Data System (ADS)

    Volkov, V.; Petrov, V. M.; Atkinson, T.; Matveenko, A.

    2016-10-01

    This article presents a novel design for a superconducting rf electron injector that incorporates energy recovery. This concept relaxes the demands of high power input couplers, improves essential beam parameters and energy efficiency and reduces the overall cost of a compact energy recovery linac machine.

  8. Teaching about Energy

    ERIC Educational Resources Information Center

    Roeder, John L.

    2009-01-01

    Energy is a fundamental concept in physics, playing an important role in every aspect of the world around us. The conversion of energy among its many forms has enabled both the sustenance of living organisms on Earth and our development of a society based on the manufacture of products for our own convenience. All of these aspects of energy are…

  9. Annual Energy Review 2002

    SciTech Connect

    Seiferlein, Katherine E.

    2003-10-01

    The Annual Energy Review (AER) presents the Energy Information Administration’s historical energy statistics. For many series, statistics are given for every year from 1949 through 2002. The statistics, expressed in either physical units or British thermal units, cover all major energy activities, including consumption, production, trade, stocks, and prices, for all major energy commodities, including fossil fuels, electricity, and renewable energy sources. Publication of this report is required under Public Law 95–91 (Department of Energy Organization Act), Section 205(c), and is in keeping with responsibilities given to the Energy Information Administration (EIA) under Section 205(a)(2), which states: “The Administrator shall be responsible for carrying out a central, comprehensive, and unified energy data and information program which will collect, evaluate, assemble, analyze, and disseminate data and information....” The AER is intended for use by Members of Congress, Federal and State agencies, energy analysts, and the general public. EIA welcomes suggestions from readers regarding data series in the AER and in other EIA publications. Related Publication: Readers of the AER may also be interested in EIA’s Monthly Energy Review, which presents monthly updates of many of the data in the AER. Contact our National Energy Information Center for more information.

  10. Energy for Education

    ERIC Educational Resources Information Center

    Cook, Emma

    2011-01-01

    Increased energy efficiency and reduced reliance on fossil fuels are both essential if people are to have any chance of avoiding escalating energy prices and the grim reality of catastrophic climate change. By increasing the diversity of energy sources people can also achieve increased security, reducing their dependence on imports. As…

  11. Solar Energy Development Progresses

    ERIC Educational Resources Information Center

    Chemical and Engineering News, 1975

    1975-01-01

    Discusses an engineering conference at which participants agreed that solar energy is a feasible energy source, although costs of such technology are presently very high. Also describes recent developments in solar energy research, and estimates the costs of this technology. (MLH)

  12. Energy Matters - Spring 2002

    SciTech Connect

    2002-03-01

    Quarterly newsletter from DOE's Industrial Technologies Program to promote the use of energy-efficient industrial systems. The focus of the Spring 2002 Issue of Energy Matters focuses on premium energy efficiency systems, with articles on new gas technologies, steam efficiency, the Augusta Newsprint Showcase, and more.

  13. World Energy Strategies

    ERIC Educational Resources Information Center

    Lovins, Amory B.

    1974-01-01

    Examines possible energy options and outlines assessments and conclusions influencing recent top level energy thinking and planning. Indicates that no nation on earth appears to have either a coherent long-range energy strategy or the institutions needed to devise one. (JR)

  14. Energy and National Security

    ERIC Educational Resources Information Center

    Abelson, Philip H.

    1973-01-01

    Discussed in this editorial is the need for a broad and detailed government policy on energy use. Oil companies can not be given complete responsibility to demonstrate usage of different energy sources. The government should construct plants because energy is connected with national security. (PS)

  15. ENERGY EFFICIENT LAUNDRY PROCESS

    SciTech Connect

    Tim Richter

    2005-04-01

    With the rising cost of energy and increased concerns for pollution and greenhouse gas emissions from power generation, increased focus is being put on energy efficiency. This study looks at several approaches to reducing energy consumption in clothes care appliances by considering the appliances and laundry chemistry as a system, rather than individually.

  16. Energy: An Overview.

    ERIC Educational Resources Information Center

    Qayoumi, Mohammad H.

    2003-01-01

    Reviews transformations in the field of energy over the last 30 years, including the 1970s energy crisis and the legislative response, the abandonment of nuclear energy, growing dependence on natural gas, growing dependence on electricity rather than oil, and superconducting technologies. (EV)

  17. Renewable Energy Annual

    EIA Publications

    2012-01-01

    Presents five chapters covering various aspects of the renewable energy marketplace, along with detailed data tables and graphics. Particular focus is given to renewable energy trends in consumption and electricity; manufacturing activities of solar thermal collectors, solar photovoltaic cells/modules, and geothermal heat pumps; and green pricing and net metering programs. The Department of Energy provides detailed offshore

  18. Renewable Energy in Alaska

    SciTech Connect

    Not Available

    2013-03-01

    This report examines the opportunities, challenges, and costs associated with renewable energy implementation in Alaska and provides strategies that position Alaska's accumulating knowledge in renewable energy development for export to the rapidly growing energy/electric markets of the developing world.

  19. Energy Drinks. Prevention Update

    ERIC Educational Resources Information Center

    Higher Education Center for Alcohol, Drug Abuse, and Violence Prevention, 2010

    2010-01-01

    High-caffeine soft drinks have existed in the United States since at least the 1980s beginning with Jolt Cola. Energy drinks, which have caffeine as their primary "energy" component, began being marketed as a separate beverage category in the United States in 1997 with the introduction of the Austrian import Red Bull. Energy drink consumption and…

  20. The Energy Primer.

    ERIC Educational Resources Information Center

    Tennessee Valley Authority, Chattanooga. Div. of Power Utilization.

    This publication is an information source on energy for teachers. The information in this publication is factual, and designed for courses of study about energy. This book has been divided into separate energy-related sections. Each section ends with a list of student participation discussion activities. The sections present facts about: (1)…

  1. School District Energy Manual.

    ERIC Educational Resources Information Center

    Association of School Business Officials International, Reston, VA.

    This manual serves as an energy conservation reference and management guide for school districts. The School District Energy Program (SDEP) is designed to provide information and/or assistance to school administrators planning to implement a comprehensive energy management program. The manual consists of 15 parts. Part 1 describes the SDEP; Parts…

  2. Energy Systems Laboratory Groundbreaking

    ScienceCinema

    Hill, David; Otter, C.L.; Simpson, Mike; Rogers, J.W.

    2016-07-12

    INL recently broke ground for a research facility that will house research programs for bioenergy, advanced battery systems, and new hybrid energy systems that integrate renewable, fossil and nuclear energy sources. Here's video from the groundbreaking ceremony for INL's new Energy Systems Laboratory. You can learn more about CAES research at http://www.facebook.com/idahonationallaboratory.

  3. Energy Matters - Fall 2002

    SciTech Connect

    2002-09-01

    Quarterly newsletter from DOE's Industrial Technologies Program to promote the use of energy-efficient industrial systems. This issue focus of this edition of the Energy Matters Newsletter is on energy and environmental issues. Read more about compressed air's role in productivity, making good motor decisions, and more.

  4. Tips for Energy Savers.

    ERIC Educational Resources Information Center

    Department of Energy, Washington, DC.

    According to 1986 U.S. Department of Energy data, 48% of our residential energy is used to heat and cool our homes, 16% goes for heating water, 12% is used to refrigerators and freezers, and the remaining 24% goes into lighting, cooking, and running appliances. This booklet contains tips for saving energy, including sections on: (1) draft-proof…

  5. Total Energy Systems.

    ERIC Educational Resources Information Center

    Hick, Basil L.

    A total energy system is a means for providing all of the varied energy requirements for a total plant from a single fuel source. This report evaluates some of the factors which are related to the development and use of total energy systems. The factors include--(1) initial and ultimate size of plant, (2) type and source of fuel, (3)…

  6. The Global Energy Budget.

    ERIC Educational Resources Information Center

    Jax, Daniel W.

    1992-01-01

    Presents a lesson plan about greenhouse effect and global warming. Includes diagrams and graphs from which students are asked to make inferences. Provides background information about how energy enters and leaves the earth system, the energy budget, consequences of obstructing the energy balance, and the greenhouse effect. (three references) (MCO)

  7. A Solar Energy Bibliography.

    ERIC Educational Resources Information Center

    Guthrie, David L.; Riley, Robert A.

    This document contains 5,000 references to literature through 1976 dealing with various aspects of solar energy. Categories are established according to area of solar research. These categories include: (1) overview; (2) measurement; (3) low-range solar energy collection (below 120 degrees C); (4) intermediate-range solar energy collection (120…

  8. Strategies for Energy Use.

    ERIC Educational Resources Information Center

    Gibbons, John H.; And Others

    1989-01-01

    Discusses the efficient use of energy. Compares reserves and pollutants generated by natural gas, oil, and coal. Points out some alternative energy sources and ways for improving energy efficiency in buildings, industrial processes, and transportation. Describes some problems in developing and developed countries. (YP)

  9. Geothermal energy in Nevada

    SciTech Connect

    Not Available

    1980-01-01

    The nature of goethermal resources in Nevada and resource applications are discussed. The social and economic advantages of utilizing geothermal energy are outlined. Federal and State programs established to foster the development of geothermal energy are discussed. The names, addresses, and phone numbers of various organizations actively involved in research, regulation, and the development of geothermal energy are included. (MHR)

  10. Energy conversion alternatives study

    NASA Technical Reports Server (NTRS)

    Shure, L. T.

    1979-01-01

    Comparison of coal based energy systems is given. Study identifies and compares various advanced energy conversion systems using coal or coal derived fuels for baselaoad electric power generation. Energy Conversion Alternatives Study (ECAS) reports provede government, industry, and general public with technically consistent basis for comparison of system's options of interest for fossilfired electric-utility application.

  11. Energy and Change

    ERIC Educational Resources Information Center

    Hecht, Eugene

    2007-01-01

    When Feynman wrote, "It is important to realize that in physics today, we have no knowledge of what energy is," he was recognizing that although we have expressions for various forms of energy from kinetic to elastic, we seem to have no idea of what the all-encompassing notion of "energy" "is": This paper addresses that issue offering a definition…

  12. Energy Tracking Diagrams

    ERIC Educational Resources Information Center

    Scherr, Rachel E.; Harrer, Benedikt W.; Close, Hunter G.; Daane, Abigail R.; DeWater, Lezlie S.; Robertson, Amy D.; Seeley, Lane; Vokos, Stamatis

    2016-01-01

    Energy is a crosscutting concept in science and features prominently in national science education documents. In the "Next Generation Science Standards," the primary conceptual learning goal is for learners to conserve energy as they "track" the transfers and transformations of energy within, into, or out of the system of…

  13. Foundry energy conservation workbook

    SciTech Connect

    Not Available

    1990-12-31

    This report discusses methods for promoting energy conservation in foundries. Use of electric power, natural gas, and coke are evaluated. Waste heat recovery systems are considered. Energy consumption in the specific processes of electric melting, natural gas melting, heat treatments, ladle melting, and coke fuel melting is described. An example energy analysis is included. (GHH)

  14. Foundry energy conservation workbook

    SciTech Connect

    1990-10-01

    This report discusses methods for promoting energy conservation in foundries. Use of electric power, natural gas, and coke are evaluated. Waste heat recovery systems are considered. Energy consumption in the specific processes of electric melting, natural gas melting, heat treatments, ladle melting, and coke fuel melting is described. An example energy analysis is included. (GHH)

  15. Renewable Energy Technology

    ERIC Educational Resources Information Center

    Daugherty, Michael K.; Carter, Vinson R.

    2010-01-01

    In many ways the field of renewable energy technology is being introduced to a society that has little knowledge or background with anything beyond traditional exhaustible forms of energy and power. Dotson (2009) noted that the real challenge is to inform and educate the citizenry of the renewable energy potential through the development of…

  16. Solar Energy and You.

    ERIC Educational Resources Information Center

    Conservation and Renewable Energy Inquiry and Referral Service (DOE), Silver Spring, MD.

    This booklet provides an introduction to solar energy by discussing: (1) how a home is heated; (2) how solar energy can help in the heating process; (3) the characteristics of passive solar houses; (4) the characteristics of active solar houses; (5) how solar heat is stored; and (6) other uses of solar energy. Also provided are 10 questions to…

  17. Energy information directory 1995

    SciTech Connect

    1995-10-01

    The National Energy Information Center provides energy information and referral assistance to Federal, State, and local governments, the academic community, business and industrial organizations, and the general public. This Energy Information Directory is used to assist the Center staff as well as other DOE staff in directing inquires to the proper offices.

  18. Our Energy Options.

    ERIC Educational Resources Information Center

    Meyers, Paul A.; Witt, Frank C.

    Presented is an analysis of alternatives available to the United States in dealing with energy problems. Options explained and evaluated include coal, solar, hydroelectric, nuclear, geothermal, wind, biomass, and energy conservation. The booklet is part of Project APEC (America's Possible Energy Choices), a nationally validated Title IVc project…

  19. Idaho's Energy Options

    SciTech Connect

    Robert M. Neilson

    2006-03-01

    This report, developed by the Idaho National Laboratory, is provided as an introduction to and an update of the status of technologies for the generation and use of energy. Its purpose is to provide information useful for identifying and evaluating Idaho’s energy options, and for developing and implementing Idaho’s energy direction and policies.

  20. Energy Systems Laboratory Groundbreaking

    SciTech Connect

    Hill, David; Otter, C.L.; Simpson, Mike; Rogers, J.W.

    2011-01-01

    INL recently broke ground for a research facility that will house research programs for bioenergy, advanced battery systems, and new hybrid energy systems that integrate renewable, fossil and nuclear energy sources. Here's video from the groundbreaking ceremony for INL's new Energy Systems Laboratory. You can learn more about CAES research at http://www.facebook.com/idahonationallaboratory.

  1. Energy Sources and Development.

    ERIC Educational Resources Information Center

    Crank, Ron

    This instructional unit is one of 10 developed by students on various energy-related areas that deals specifically with energy sources and development. Its objective is for the student to be able to discuss energy sources and development related to the historical perspective, biological development, current aspects, and future expectations…

  2. Energy and Economic Growth.

    ERIC Educational Resources Information Center

    Sonenblum, Sidney

    This report reviews the economic impacts of the energy dilemma. Presented are viewpoints that have emerged relating to: (1) the desirability of economic growth; (2) the relationship between economic growth and energy usage; (3) the effects of energy wage in limiting or expanding the opportunities for growth; and (4) whether there is some sense in…

  3. Minnesota and Energy.

    ERIC Educational Resources Information Center

    Minnesota State Dept. of Natural Resources, St. Paul. Environmental Education Board.

    Eight energy education activities are provided. Each activity includes an overview, a brief summary, lists of objectives and materials needed, teacher's notes, and student materials. The activities focus on: (1) using social studies skills to understand Minnesota energy data and to clarify and understand some Minnesota energy issues; (2) giving…

  4. Energy-Water Nexus

    SciTech Connect

    Horak, W.

    2010-07-26

    Conclusions of this presentation are: (1) energy and water are interconnected; (2) new energy sources will place increased demands on water supplies; (3) existing energy sources will be subjected to increasing restrictions on their water use; and (4) integrated decision support tools will need to be developed to help policy makers decide which policies and advanced technologies can address these issues.

  5. Plugging into Energy Savings.

    ERIC Educational Resources Information Center

    Harrigan, Merrilee

    1999-01-01

    The nonprofit Alliance to Save Energy has been helping schools reduce energy consumption through a combination of retrofits, classroom instruction, and behavior. Lists eight small steps to big energy savings, among them: involve the whole school, stop leaks, turn off computers, and recycle. (MLF)

  6. Chapter 3: Energy Security

    SciTech Connect

    Foust, Thomas D.; Arent, Doug; de Carvalho Macedo, Isaias; Goldemberg, Jose; Hoysala, Chanakya; Filho, Rubens Maciel; Nigro, Francisco E. B.; Richard, Tom L.; Saddler, Jack; Samseth, Jon; Somerville, Chris R.

    2015-04-01

    This chapter considers the energy security implications and impacts of bioenergy. We provide an assessment to answer the following questions: What are the implications for bioenergy and energy security within the broader policy environment that includes food and water security, development, economic productivity, and multiple foreign policy aspects? What are the conditions under which bioenergy contributes positively to energy security?

  7. Energy Savers: Tips on Saving Money & Energy at Home

    SciTech Connect

    2014-05-01

    Provides consumers with home energy and money savings tips such as insulation, weatherization, heating, cooling, water heating, energy efficient windows, landscaping, lighting, and energy efficient appliances.

  8. Energy Savers: Tips on Saving Money & Energy at Home

    SciTech Connect

    2011-12-01

    Provides consumers with home energy and money savings tips such as insulation, weatherization, heating, cooling, water heating, energy efficient windows, landscaping, lighting, and energy efficient appliances.

  9. Magnetic resonance energy and topological resonance energy.

    PubMed

    Aihara, Jun-Ichi

    2016-04-28

    Ring-current diamagnetism of a polycyclic π-system is closely associated with thermodynamic stability due to the individual circuits. Magnetic resonance energy (MRE), derived from the ring-current diamagnetic susceptibility, was explored in conjunction with graph-theoretically defined topological resonance energy (TRE). For many aromatic molecules, MRE is highly correlative with TRE with a correlation coefficient of 0.996. For all π-systems studied, MRE has the same sign as TRE. The only trouble with MRE may be that some antiaromatic and non-alternant species exhibit unusually large MRE-to-TRE ratios. This kind of difficulty can in principle be overcome by prior geometry-optimisation or by changing spin multiplicity. Apart from the semi-empirical resonance-theory resonance energy, MRE is considered as the first aromatic stabilisation energy (ASE) defined without referring to any hypothetical polyene reference.

  10. Wind energy: Developing energy, wealth, and change

    NASA Astrophysics Data System (ADS)

    Hopkins, Matt

    Wind energy has emerged as one of the fastest growing energy sources in the United States over the course of the last decade. It is the renewable energy type most readily defining clean economy leadership. An uncertain policy context, public conflicts over the impacts of turbine installations, and unsorted connections to a national green development strategy raise questions about the continued viability of wind power in the U.S. This thesis attempts to document and question some of the issues raised by wind energy expansion in the U.S. generally, but in Maine in particular, in order to explain how environmental, social, and economic benefits accrue to places hosting wind projects. The available information combined with a targeted inquiry produce insights into how the state of Maine can improve its wind development policies and outcomes.

  11. Non-conventional energy sources

    SciTech Connect

    Furlan, G.; Rodriguez, H.; Violini, G.

    1982-01-01

    This book presents the papers given at a conference on renewable energy sources. Topics considered at the conference included the estimate of global and diffuse radiation, thin films in photothermal solar energy conversion, solar collectors, prospects for photovoltaic products in the developing countries, passive energy systems in buildings, hydrogen fuels, geothermal energy, wind energy, tidal energy, and wave energy in developing countries.

  12. Energy 83. Revised and Expanded.

    ERIC Educational Resources Information Center

    Lord, John, Ed.

    Energy 80 is an energy education program for middle/junior high school students. This document is a booklet of energy topics designed for student use in the program. Topics considered in this booklet include: forms of energy; energy rules; solar energy; food energy; fossil fuels; coal; oil and gas production and consumption; nuclear fission;…

  13. Fort Sill Tribal Energy Plan

    SciTech Connect

    Shamieka Ross

    2006-06-26

    The Fort Sill Apache Tribe of Oklahoma has concluded an energy project funded through the “First Steps Toward Developing Renewable Energy & Energy Efficiency” program provided by the Department of Energy. The intent of the project was to include the establishment of a tribal Energy Office, an energy audit of tribal facilities, and a Strategic Energy Plan.

  14. Monthly energy review, December 1993

    SciTech Connect

    Not Available

    1993-12-22

    This document provides data on monthly energy use and fossil fuels. The following sections are included: Highlights: Emissions of greenhouse gases in the United States 1985--1990; Highlights: assessment of energy use in multibuilding facilities; energy overview; energy consumption; petroleum; natural gas; oil and gas resource development; coal; electricity; nuclear energy; energy prices; and international energy.

  15. Monthly energy review, April 1994

    SciTech Connect

    Not Available

    1994-04-01

    The Monthly Energy Review contains statistical data on the following: energy consumption, petroleum, natural gas, oil and gas resource development, coal, electricity, nuclear energy, energy prices, and international energy. In addition, an energy overview is provided, and, for the April issue, Energy use and carbon emissions; Some international comparisons.

  16. Annual energy review 2003

    SciTech Connect

    Seiferlein, Katherin E.

    2004-09-30

    The Annual Energy Review 2003 is a statistical history of energy activities in the United States in modern times. Data are presented for all major forms of energy by production (extraction of energy from the earth, water, and other parts of the environment), consumption by end-user sector, trade with other nations, storage changes, and pricing. Much of the data provided covers the fossil fuels—coal, petroleum, and natural gas. Fossil fuels are nature’s batteries; they have stored the sun’s energy over millennia past. It is primarily that captured energy that we are drawing on today to fuel the activities of the modern economy. Data in this report measure the extraordinary expansion of our use of fossil fuels from 29 quadrillion British thermal units (Btu) in 1949 to 84 quadrillion Btu in 2003. In recent years, fossil fuels accounted for 86 percent of all energy consumed in the United States. This report also records the development of an entirely new energy industry—the nuclear electric power industry. The industry got its start in this country in 1957 when the Shippingport, Pennsylvania, nuclear electric power plant came on line. Since that time, the industry has grown to account for 20 percent of our electrical output and 8 percent of all energy used in the country. Renewable energy is a third major category of energy reported in this volume. Unlike fossil fuels, which are finite in supply, renewable energy is essentially inexhaustible because it can be replenished. Types of energy covered in the renewable category include conventional hydroelectric power, which is power derived from falling water; wood; waste; alcohol fuels; geothermal; solar; and wind. Together, these forms of energy accounted for about 6 percent of all U.S. energy consumption in recent years.

  17. Science Activities in Energy: Solar Energy II.

    ERIC Educational Resources Information Center

    Oak Ridge Associated Universities, TN.

    Included in this science activities energy package are 14 activities related to solar energy for secondary students. Each activity is outlined on a single card and is introduced by a question such as: (1) how much solar heat comes from the sun? or (2) how many times do you have to run water through a flat-plate collector to get a 10 degree rise in…

  18. National Energy Audit

    SciTech Connect

    Gettings, Michael B.

    2001-12-30

    A user-friendly, advanced computer energy audit, the National Energy Audit (NEAT) has been developed by the Existing Buildings Research Program at Oak Ridge National Laboratory''s (ORNL''s) Building Technology Center for the U.S. Department of Energy''s (DOE''s) Weatherization Assistance and Existing Buildings Program. The computer program is designed for use by State agencies and utilities to determine the most cost-effective retrofit measures for single-family homes to increase the energy efficiency and comfort level. NEAT7.1.3 contains minor changes and improvements in NEAT7.1.

  19. Annual Energy Review 2001

    SciTech Connect

    Seiferlein, Katherine E.

    2002-11-01

    The Annual Energy Review (AER) is a statistical history of energy activities in the United States. It documents trends and milestones in U.S. energy production, trade, storage, pricing, and consumption. Each new year of data that is added to the time series—which now reach into 7 decades—extends the story of how Americans have acquired and used energy. It is a story of continual change as the Nation's economy grew, energy requirements expanded, resource availability shifted, and interdependencies developed among nations.

  20. Energy Facts, 1992

    SciTech Connect

    Not Available

    1993-10-29

    Energy Facts, organized by energy source, is a compilation of energy data providing a reference to a broad range of domestic and international energy data, for the general public as well as the technical community. This report is designed especially for the business person, government worker, or student who needs a quick reference to major facts about energy. Each table of statistics appears on the opposite page from a corresponding graphic. The graphic has a point of interest rather than a title across the top.

  1. Geothermal Energy; (USA)

    SciTech Connect

    Raridon, M.H.; Hicks, S.C.

    1991-01-01

    Geothermal Energy (GET) announces on a bimonthly basis the current worldwide information available on the technologies required for economic recovery of geothermal energy and its use as direct heat or for electric power production. This publication contains the abstracts of DOE reports, journal article, conference papers, patents, theses, and monographs added to the Energy Science and Technology Database (EDB) during the past two months. Also included are US information obtained through acquisition programs or interagency agreements and international information obtained through the International Energy Agency's Energy Technology Data Exchange or government-to-government agreements.

  2. State energy overview

    SciTech Connect

    Not Available

    1982-09-01

    This publication presents an overview of selected energy-related data for the United States, for each State, and for the District of Columbia. Included are the quantities of energy produced and consumed, estimates of fuel reserves, and the value of nonrenewable fuels produced by type. Also provided for each State are selected demographic and energy-related information that have been ranked and expressed as a percent of the national total. This overview provides a ready reference and a quick access to selected State energy information and State rankings for various socioeconomics and energy items.

  3. State Energy Overview 1982

    SciTech Connect

    Not Available

    1984-08-01

    Data are presented for the 50 states and the District of Columbia. Included are the quantities of energy produced and consumed, estimates of fuel reserves, the value of nonrenewable fuels produced by type, energy expenditures, and consumer prices. Also provided for each state are selected demographic and energy-related data that have been ranked and expressed as a percent of the national total. This overview provides a ready reference and a quick access to selected state energy information and state rankings for various socioeconomic and energy items. Methodology is detailed; a glossary is provided.

  4. National Energy Audit

    2001-12-30

    A user-friendly, advanced computer energy audit, the National Energy Audit (NEAT) has been developed by the Existing Buildings Research Program at Oak Ridge National Laboratory''s (ORNL''s) Building Technology Center for the U.S. Department of Energy''s (DOE''s) Weatherization Assistance and Existing Buildings Program. The computer program is designed for use by State agencies and utilities to determine the most cost-effective retrofit measures for single-family homes to increase the energy efficiency and comfort level. NEAT7.1.3 contains minormore » changes and improvements in NEAT7.1.« less

  5. Colorado's clean energy choices

    SciTech Connect

    Strawn, N.; Jones, J.

    2000-04-15

    The daily choices made as consumers affect the environment and the economy. Based on the state of today's technology and economics, Colorado consumers can include energy efficiency and renewable energy into many aspects of their lives. These choices include where they obtain electricity, how they use energy at home, and how they transport themselves from one place to another. In addition to outlining how they can use clean energy, Colorado's Clean Energy Choices gives consumers contacts and links to Web sites for where to get more information.

  6. Annual Energy Outlook

    EIA Publications

    2015-01-01

    The projections in the U.S. Energy Information Administration's (EIA's) Annual Energy Outlook 2015 (AEO2015) focus on the factors that shape the U.S. energy system over the long term. For the first time, the Annual Energy Outlook (AEO) is presented as a shorter edition under a newly adopted two-year release cycle. With this approach, full editions and shorter editions of the AEO will be produced in alternating years. This approach will allow EIA to focus more resources on rapidly changing energy markets both in the United States and internationally, and to consider how they might evolve over the next few years.

  7. International energy outlook 1999

    SciTech Connect

    1999-03-01

    This report presents international energy projections through 2020, prepared by the Energy Information Administration. The outlooks for major energy fuels are discussed, along with electricity, transportation, and environmental issues. The report begins with a review of world trends in energy demand. The historical time frame begins with data from 1970 and extends to 1996, providing readers with a 26-year historical view of energy demand. The IEO99 projections covers a 24-year period. The next part of the report is organized by energy source. Regional consumption projections for oil, natural gas, coal, nuclear power, and renewable energy (hydroelectricity, geothermal, wind, solar, and other renewables) are presented in the five fuel chapters, along with a review of the current status of each fuel on a worldwide basis. The third part of the report looks at energy consumption in the end-use sectors, beginning with a chapter on energy use for electricity generation. New to this year`s outlook are chapters on energy use in the transportation sector and on environmental issues related to energy consumption. 104 figs., 87 tabs.

  8. Annual Energy Review 2009

    SciTech Connect

    Fichman, Barbara T.

    2010-08-01

    The Annual Energy Review (AER) is the U.S. Energy Information Administration's (EIA) primary report of annual historical energy statistics. For many series, data begin with the year 1949. Included are statistics on total energy production, consumption, trade, and energy prices; overviews of petroleum, natural gas, coal, electricity, nuclear energy, renewable energy, and international energy; financial and environment indicators; and data unit conversions. Publication of this report is required under Public Law 95–91 (Department of Energy Organization Act), Section 205(c), and is in keeping with responsibilities given to the EIA under Section 205(a)(2), which states: “The Administrator shall be responsible for carrying out a central, comprehensive, and unified energy data and information program which will collect, evaluate, assemble, analyze, and disseminate data and information....” The AER is intended for use by Members of Congress, Federal and State agencies, energy analysts, and the general public. EIA welcomes suggestions from readers regarding the content of the AER and other EIA publications.

  9. China energy databook

    SciTech Connect

    Sinton, J.E.; Levine, M.D.; Feng Liu; Davis, W.B. ); Jiang Zhenping; Zhuang Xing; Jiang Kejun; Zhou Dadi )

    1992-11-01

    The Energy Analysis Program (EAP) at the Lawrence Berkeley Laboratory (LBL) first becamc involved in Chinese energy issues through a joint China-US symposium on markets and demand for energy held in Nanjing in November of 1988. Discovering common interests, EAP began to collaborate on projects with the Energy Research Institute (ERI) of China's State Planning Commission. In the course of this work it became clear that a major issue in the furtherance of our research was the acquisition of reliable data. In addition to other, more focused activities-evaluating programs of energy conservation undertaken in China and the prospects for making Chinese industries more energy-efficient, preparing historical reviews of energy supply and demand in the People's Republic of China, sponsoring researchers from China to work with experts at LBL on such topics as energy efficiency standards for buildings, adaptation of US energy analysis software to Chinese conditions, and transportation issues-we decided to compile, assess, and organize Chinese energy data. We are hopeful that this volume will not only help us in our work, but help build a broader community of Chinese energy policy studies within the US.

  10. German energy technology prospects.

    PubMed

    Popp, M

    1982-12-24

    After more than 25 years of development of nuclear power and almost 10 years of research and development in numerous areas of nonnuclear energy, there is now a good basis for judging the future prospects of energy technologies in the Federal Republic of Germany. The development of nuclear power has provided an important and economically advantageous new source of energy. Further efforts are needed to establish the nuclear fuel cycle in all stages and to exploit the potential of advanced reactors. In all other areas of energy technology, including energy conservation, new energy sources, and coal, economics has turned out to be the key problem, even at today's energy prices. Opportunities to overcome these economic problems through additional R & D are limited. There is some potential for special applications, and there are many technologies that could contribute to the energy supply of developing countries. In general, however, progress in energy conservation and the use of renewable energy sources will depend on the degree to which energy policy measures can improve their economic basis. For some technologies, such as solar thermal power stations and coal liquefaction, large-scale economic deployment cannot be foreseen today. Instead of establishing costly demonstration projects, emphasis will be put on improving key components of these technologies with the aim of having the most advanced technology available when the economic parameters are more favorable. PMID:17770150

  11. German energy technology prospects.

    PubMed

    Popp, M

    1982-12-24

    After more than 25 years of development of nuclear power and almost 10 years of research and development in numerous areas of nonnuclear energy, there is now a good basis for judging the future prospects of energy technologies in the Federal Republic of Germany. The development of nuclear power has provided an important and economically advantageous new source of energy. Further efforts are needed to establish the nuclear fuel cycle in all stages and to exploit the potential of advanced reactors. In all other areas of energy technology, including energy conservation, new energy sources, and coal, economics has turned out to be the key problem, even at today's energy prices. Opportunities to overcome these economic problems through additional R & D are limited. There is some potential for special applications, and there are many technologies that could contribute to the energy supply of developing countries. In general, however, progress in energy conservation and the use of renewable energy sources will depend on the degree to which energy policy measures can improve their economic basis. For some technologies, such as solar thermal power stations and coal liquefaction, large-scale economic deployment cannot be foreseen today. Instead of establishing costly demonstration projects, emphasis will be put on improving key components of these technologies with the aim of having the most advanced technology available when the economic parameters are more favorable.

  12. Remanufacturing and energy savings.

    PubMed

    Gutowski, Timothy G; Sahni, Sahil; Boustani, Avid; Graves, Stephen C

    2011-05-15

    Remanufactured products that can substitute for new products are generally claimed to save energy. These claims are made from studies that look mainly at the differences in materials production and manufacturing. However, when the use phase is included, the situation can change radically. In this Article, 25 case studies for eight different product categories were studied, including: (1) furniture, (2) clothing, (3) computers, (4) electric motors, (5) tires, (6) appliances, (7) engines, and (8) toner cartridges. For most of these products, the use phase energy dominates that for materials production and manufacturing combined. As a result, small changes in use phase efficiency can overwhelm the claimed savings from materials production and manufacturing. These use phase energy changes are primarily due to efficiency improvements in new products, and efficiency degradation in remanufactured products. For those products with no, or an unchanging, use phase energy requirement, remanufacturing can save energy. For the 25 cases, we found that 8 cases clearly saved energy, 6 did not, and 11 were too close to call. In some cases, we could examine how the energy savings potential of remanufacturing has changed over time. Specifically, during times of significant improvements in energy efficiency, remanufacturing would often not save energy. A general design trend seems to be to add power to a previously unpowered product, and then to improve on the energy efficiency of the product over time. These trends tend to undermine the energy savings potential of remanufacturing.

  13. Guam Energy Action Plan

    SciTech Connect

    Conrad, M. D.; Ness, J. E.

    2013-07-01

    Describes the four near-term strategies selected by the Guam Energy Task Force during action planning workshops conducted in March 2013, and outlines the steps being taken to implement those strategies. Each strategy addresses one of the energy sectors identified in the earlier Guam strategic energy plan as being an essential component of diversifying Guam's fuel sources and reducing fossil energy consumption 20% by 2020. The four energy strategies selected are: (1) expanding public outreach on energy efficiency and conservation, (2) establishing a demand-side management revolving loan program, (3) exploring waste-to-energy options, and (4) influencing the transportation sector via anti-idling legislation, vehicle registration fees, and electric vehicles.

  14. Energy Sector Market Analysis

    SciTech Connect

    Arent, D.; Benioff, R.; Mosey, G.; Bird, L.; Brown, J.; Brown, E.; Vimmerstedt, L.; Aabakken, J.; Parks, K.; Lapsa, M.; Davis, S.; Olszewski, M.; Cox, D.; McElhaney, K.; Hadley, S.; Hostick, D.; Nicholls, A.; McDonald, S.; Holloman, B.

    2006-10-01

    This paper presents the results of energy market analysis sponsored by the Department of Energy's (DOE) Weatherization and International Program (WIP) within the Office of Energy Efficiency and Renewable Energy (EERE). The analysis was conducted by a team of DOE laboratory experts from the National Renewable Energy Laboratory (NREL), Oak Ridge National Laboratory (ORNL), and Pacific Northwest National Laboratory (PNNL), with additional input from Lawrence Berkeley National Laboratory (LBNL). The analysis was structured to identify those markets and niches where government can create the biggest impact by informing management decisions in the private and public sectors. The analysis identifies those markets and niches where opportunities exist for increasing energy efficiency and renewable energy use.

  15. The frontiers of energy

    NASA Astrophysics Data System (ADS)

    Armstrong, Robert C.; Wolfram, Catherine; de Jong, Krijn P.; Gross, Robert; Lewis, Nathan S.; Boardman, Brenda; Ragauskas, Arthur J.; Ehrhardt-Martinez, Karen; Crabtree, George; Ramana, M. V.

    2016-01-01

    Great strides have been made over the past century in our ability to harness energy sources, leading to profound transformations — both good and bad — in society. Looking at the energy system of today, it is clear that meeting the energy needs of the world now and in the years to come requires the concerted efforts of many different actors across a range of technologies and approaches. In this Feature, ten leading experts in energy research share their vision of what challenges their respective fields need to address in the coming decades. The issues being faced are diverse and multifaceted, from the search for better materials for fuels, to the design of energy policy and markets for the developing world. However, a common theme emerges: changes to adapt and improve our energy system are greatly needed. By improving our mutual understanding of the issues faced by each area of energy research, these changes can happen more smoothly, efficiently and rapidly.

  16. Annual Energy Review, 1995

    SciTech Connect

    1996-07-01

    This document presents statistics on energy useage for 1995. A reviving domestic economy, generally low energy prices, a heat wave in July and August, and unusually cold weather in November and December all contributed to the fourth consecutive year of growth in U.S. total energy consumption, which rose to an all-time high of almost 91 quadrillion Btu in 1995 (1.3). The increase came as a result of increases in the consumption of natural gas, coal, nuclear electric power, and renewable energy. Petroleum was the primary exception, and its use declined by only 0.3 percent. (Integrating the amount of renewable energy consumed outside the electric utility sector into U.S. total energy consumption boosted the total by about 3.4 quadrillion Btu, but even without that integration, U.S. total energy consumption would have reached a record level in 1995.)

  17. International energy annual 1997

    SciTech Connect

    1999-04-01

    The International Energy Annual presents an overview of key international energy trends for production, consumption, imports, and exports of primary energy commodities in over 220 countries, dependencies, and areas of special sovereignty. Also included are population and gross domestic product data, as well as prices for crude oil and petroleum products in selected countries. Renewable energy reported in the International Energy Annual includes hydroelectric power and geothermal, solar, and wind electric power. Also included are biomass electric power for Brazil and the US, and biomass, geothermal, and solar energy produced in the US and not used for electricity generation. This report is published to keep the public and other interested parties fully informed of primary energy supplies on a global basis. The data presented have been largely derived from published sources. The data have been converted to units of measurement and thermal values (Appendices E and F) familiar to the American public. 93 tabs.

  18. Solar thermal energy receiver

    NASA Technical Reports Server (NTRS)

    Baker, Karl W. (Inventor); Dustin, Miles O. (Inventor)

    1992-01-01

    A plurality of heat pipes in a shell receive concentrated solar energy and transfer the energy to a heat activated system. To provide for even distribution of the energy despite uneven impingement of solar energy on the heat pipes, absence of solar energy at times, or failure of one or more of the heat pipes, energy storage means are disposed on the heat pipes which extend through a heat pipe thermal coupling means into the heat activated device. To enhance energy transfer to the heat activated device, the heat pipe coupling cavity means may be provided with extensions into the device. For use with a Stirling engine having passages for working gas, heat transfer members may be positioned to contact the gas and the heat pipes. The shell may be divided into sections by transverse walls. To prevent cavity working fluid from collecting in the extensions, a porous body is positioned in the cavity.

  19. Building energy analysis tool

    DOEpatents

    Brackney, Larry; Parker, Andrew; Long, Nicholas; Metzger, Ian; Dean, Jesse; Lisell, Lars

    2016-04-12

    A building energy analysis system includes a building component library configured to store a plurality of building components, a modeling tool configured to access the building component library and create a building model of a building under analysis using building spatial data and using selected building components of the plurality of building components stored in the building component library, a building analysis engine configured to operate the building model and generate a baseline energy model of the building under analysis and further configured to apply one or more energy conservation measures to the baseline energy model in order to generate one or more corresponding optimized energy models, and a recommendation tool configured to assess the one or more optimized energy models against the baseline energy model and generate recommendations for substitute building components or modifications.

  20. Consumer Energy Atlas

    SciTech Connect

    Not Available

    1980-06-01

    This first edition of the Atlas provides, in reference form, a central source of information to consumers on key contacts concerned with energy in the US. Energy consumers need information appropriate to local climates and characteristics - best provided by state and local governments. The Department of Energy recognizes the authority of state and local governments to manage energy programs on their own. Therefore, emphasis has been given to government organizations on both the national and state level that influence, formulate, or administer policies affecting energy production, distribution, and use, or that provide information of interest to consumers and non-specialists. In addition, hundreds of non-government energy-related membership organizations, industry trade associations, and energy publications are included.

  1. Renewable energy annual 1995

    SciTech Connect

    1995-12-01

    The Renewable Energy Annual 1995 is the first in an expected series of annual reports the Energy Information Administration (EIA) intends to publish to provide a comprehensive assessment of renewable energy. This report presents the following information on the history, status, and prospects of renewable energy data: estimates of renewable resources; characterizations of renewable energy technologies; descriptions of industry infrastructures for individual technologies; evaluations of current market status; and assessments of near-term prospects for market growth. An international section is included, as well as two feature articles that discuss issues of importance for renewable energy as a whole. The report also contains a number of technical appendices and a glossary. The renewable energy sources included are biomass (wood), municipal solid waste, biomass-derived liquid fuels, geothermal, wind, and solar and photovoltaic.

  2. International energy outlook, 1992

    SciTech Connect

    Not Available

    1992-04-08

    This report presents the current Energy Information Administration (EIA) assessment of the long-term outlook for international energy markets. The historic political and economic changes occurring in Easter Europe and the former Soviet Union will, no doubt, transform regional markets and world trade. This report pays particular attention to energy markets and resources in those countries that were once a part of the Centrally Planned Economies (CPE's) and how prospective changes in these countries might influence the energy outlook for the rest of the world. Several major EIA estimates determine, in large part, the resulting energy projections presented here. These include estimates of the energy intensity of economic activity; oil and natural gas production capacities; nuclear and hydroelectric generation capacities; international coal trade; and the rate of incremental energy requirements met by alternatives to oil.

  3. International energy outlook, 1992

    SciTech Connect

    Not Available

    1992-04-08

    This report presents the current Energy Information Administration (EIA) assessment of the long-term outlook for international energy markets. The historic political and economic changes occurring in Easter Europe and the former Soviet Union will, no doubt, transform regional markets and world trade. This report pays particular attention to energy markets and resources in those countries that were once a part of the Centrally Planned Economies (CPE`s) and how prospective changes in these countries might influence the energy outlook for the rest of the world. Several major EIA estimates determine, in large part, the resulting energy projections presented here. These include estimates of the energy intensity of economic activity; oil and natural gas production capacities; nuclear and hydroelectric generation capacities; international coal trade; and the rate of incremental energy requirements met by alternatives to oil.

  4. Energy conservation in distillation

    NASA Astrophysics Data System (ADS)

    Mix, T. W.; Dweck, J. S.; Weinberg, M.; Armstrong, R. C.

    1981-07-01

    An audit of major industrial and processes and key colums in each major process indicated that approximately twoquads of energy were consumed for distillation in the US in 1976. Energy usage by industry is included: petroleum refineries, 66% chemical (including petrochemical) industry, 29% natural gas liquids processing, 5%. Techniques and current practices for conserving distillation energy are reviewed, and guidelines indicating those process conditons which favor the use of each energy conserving technique are enumerated. Expressions for payout time for tray and control retrofit options are developed based on energy savings and increased throughput. Calculations for industrial colums suggested that both types of retrofits would frequently have short (,6 months) payout times based on either criterion. Extractive distillation is also discussed, and criteria enabling the estimation of the energy which may be conserved using this technique are developed. Good housekeeping practices and field techniques for checking the energy efficiency of industrial distillations are also discussed.

  5. Energy and Water Management

    NASA Technical Reports Server (NTRS)

    Valek, Susan E.

    2008-01-01

    Energy efficiency isn't just a good idea; it's a necessity, both for cost reasons and to meet federal regulatory requirements. First, rising energy unit costs continue to erode NASA's mission budget. NASA spent roughly $156M on facility energy in FY 2007. Although that represents less than one per cent of NASA's overall annual budget, the upward trend in energy costs concerns the agency. While NASA reduced consumption 13%, energy unit costs have risen 63%. Energy cost increases counteract the effects of energy conservation, which results in NASA buying less yet spending more. The second factor is federal energy legislation. The National Energy Conservation Policy Act, as amended by the Energy Policy Act of 2005, Executive Order (EO) 13423 (January, 2007), and the Energy Independence and Security Act (December, 2007), mandates energy/water conservation goals for all federal agencies, including NASA. There are also reporting requirements associated with this legislation. The Energy/Water Management Task was created to support NASA Headquarters Environmental Management Division (HO EMD) in meeting these requirements. With assistance from TEERM, HQ EMD compiled and submitted the NASA Annual Report to the Department of Energy FY 2007. The report contains information on how NASA is meeting federally mandated energy and water management goals. TEERM monitored input for timeliness, errors, and conformity to the new energy/water reporting guidelines and helped compile the information into the final report. TEERM also assists NASA Energy/Water Management with proposal and award calls, updates to the energy/water management database, and facilitating communication within the energy/water management community. TEERM is also supporting NASA and the Interagency Working Group (IWG) on Hydrogen and Fuel Cells. Established shortly after the President announced the Hydrogen Fuel Initiative in 2003, this IWG serves as the mechanism for collaboration among the Federal agencies

  6. Biogas - the calculable energy

    NASA Astrophysics Data System (ADS)

    Kith, Károly; Nagy, Orsolya; Balla, Zoltán; Tamás, András

    2015-04-01

    EU actions against climate change are rising energy prices, both have emphasized the use of renewable energy,increase investments and energy efficiency. A number of objectives formulated in the EC decree no. 29/2009 by 2020. This document is based on the share of renewable energies in energy consumption should be increased to 20% (EC, 2009). The EU average is 20% but the share of renewables vary from one member state to another. In Hungary in 2020, 14.65% renewable energy share is planned to be achieved. According to the latest Eurostat data, the share of renewable energy in energy consumption of the EU average was 14.1%, while in Hungary, this share was 9.6% in 2012. (EUROSTAT, 2014). The use of renewable energy plant level is influenced by several factors. The most important of these is the cost savings and efficiency gains. Hungarian investments in renewable energy production usually have high associated costs and the payback period is substantially more than five years, depending on the support rate. For example, the payback period is also influenced by the green electricity generated feed prices, which is one of the lowest in Hungary compared the Member States of the European Union. Consequently, it is important to increase the production of green energy. Nowadays, predictable biogas energy is an outstanding type of decentralized energy production. It follows directly that agricultural by-products can be used to produce energy and they also create jobs by the construction of a biogas plant. It is important to dispose of and destroy hazardous and noxious substances in energy production. It follows from this that the construction of biogas plants have a positive impact, in addition to green energy which is prepared to reduce the load on the environment. The production of biogas and green electricity is one of the most environment friendly forms of energy production. Biogas production also has other important ecological effects, such as the substitution of

  7. Indian Renewable Energy and Energy Efficiency Policy Database (Fact Sheet)

    SciTech Connect

    Bushe, S.

    2013-09-01

    This fact sheet provides an overview of the Indian Renewable Energy and Energy Efficiency Policy Database (IREEED) developed in collaboration by the United States Department of Energy and India's Ministry of New and Renewable Energy. IREEED provides succinct summaries of India's central and state government policies and incentives related to renewable energy and energy efficiency. The online, public database was developed under the U.S.- India Energy Dialogue and the Clean Energy Solution Center.

  8. Energy Transmission and Infrastructure

    SciTech Connect

    Mathison, Jane

    2012-12-31

    The objective of Energy Transmission and Infrastructure Northern Ohio (OH) was to lay the conceptual and analytical foundation for an energy economy in northern Ohio that will: • improve the efficiency with which energy is used in the residential, commercial, industrial, agricultural, and transportation sectors for Oberlin, Ohio as a district-wide model for Congressional District OH-09; • identify the potential to deploy wind and solar technologies and the most effective configuration for the regional energy system (i.e., the ratio of distributed or centralized power generation); • analyze the potential within the district to utilize farm wastes to produce biofuels; • enhance long-term energy security by identifying ways to deploy local resources and building Ohio-based enterprises; • identify the policy, regulatory, and financial barriers impeding development of a new energy system; and • improve energy infrastructure within Congressional District OH-09. This objective of laying the foundation for a renewable energy system in Ohio was achieved through four primary areas of activity: 1. district-wide energy infrastructure assessments and alternative-energy transmission studies; 2. energy infrastructure improvement projects undertaken by American Municipal Power (AMP) affiliates in the northern Ohio communities of Elmore, Oak Harbor, and Wellington; 3. Oberlin, OH-area energy assessment initiatives; and 4. a district-wide conference held in September 2011 to disseminate year-one findings. The grant supported 17 research studies by leading energy, policy, and financial specialists, including studies on: current energy use in the district and the Oberlin area; regional potential for energy generation from renewable sources such as solar power, wind, and farm-waste; energy and transportation strategies for transitioning the City of Oberlin entirely to renewable resources and considering pedestrians, bicyclists, and public transportation as well as drivers

  9. Asian Energy Security

    SciTech Connect

    Peter Hayes, PhD

    2003-12-01

    OAK-B135 In the Asian Energy Security (AES) Project, Nautilus Institute works together with a network of collaborating groups from the countries of Northeast Asia to evaluate the energy security implications of different national and regional energy ''paths''. The goal of the Asia Energy Security project is to illuminate energy paths--and the energy policy choices that might help to bring them about--that result in a higher degree of energy security for the region and for the world as a whole, that is, to identify energy paths that are ''robust'' in meeting many different energy security and development objectives, while also offering flexibility in the face of uncertainty. In work to date, Nautilus has carefully assembled a network of colleagues from the countries of the region, trained them together as a group in the use of a common, flexible, and transparent energy and environmental analysis planning software tool (LEAP, the Long-range Energy Alternatives Planning system), and worked with them to prepare base-year energy sector models for each country. To date, complete data sets and models for ''Business as Usual'' (BAU) energy paths have been compiled for China, Japan, the Republic of Korea, and the Democratic Peoples' Republic of Korea. A partial data set and BAU path has been compiled for the Russian Far East, and a data set is being started in Mongolia, where a team of researchers has just joined the AES project. In several countries, ''Alternative'' energy paths have been developed as well, or partially elaborated. National energy sector developments, progress on national LEAP modeling, additional LEAP training, and planning for the next phase of the AES project were the topics of a recent (early November) workshop held in Vancouver, British Columbia. With funding from the Department of Energy, Nautilus is poised to build upon the successes of the project to date with a coordinated international effort to research the energy security ramifications of

  10. Broadband pendulum energy harvester

    NASA Astrophysics Data System (ADS)

    Liang, Changwei; Wu, You; Zuo, Lei

    2016-09-01

    A novel electromagnetic pendulum energy harvester with mechanical motion rectifier (MMR) is proposed and investigated in this paper. MMR is a mechanism which rectifies the bidirectional swing motion of the pendulum into unidirectional rotation of the generator by using two one-way clutches in the gear system. In this paper, two prototypes of pendulum energy harvester with MMR and without MMR are designed and fabricated. The dynamic model of the proposed MMR pendulum energy harvester is established by considering the engagement and disengagement of the one way clutches. The simulation results show that the proposed MMR pendulum energy harvester has a larger output power at high frequencies comparing with non-MMR pendulum energy harvester which benefits from the disengagement of one-way clutch during pendulum vibration. Moreover, the proposed MMR pendulum energy harvester is broadband compare with non-MMR pendulum energy harvester, especially when the equivalent inertia is large. An experiment is also conducted to compare the energy harvesting performance of these two prototypes. A flywheel is attached at the end of the generator to make the disengagement more significant. The experiment results also verify that MMR pendulum energy harvester is broadband and has a larger output power at high frequency over the non-MMR pendulum energy harvester.

  11. Ocean energy program summary

    NASA Astrophysics Data System (ADS)

    1990-01-01

    The oceans are the world's largest solar energy collector and storage system. Covering 71 percent of the earth's surface, they collect and store this energy as waves, currents, and thermal and salinity gradients. The purpose of the U.S. Department of Energy's (DOE) Ocean Energy Technology (OET) Program is to develop techniques that harness this ocean energy cost effectively and in a way that does not harm the environment. The program seeks to develop ocean energy technology to a point where industry can accurately assess whether the technology is a viable energy conversion alternative, or supplement, to current power generating systems. In past studies, DOE identified ocean thermal energy conversion (OTEC), which uses the temperature difference between warm surface water and cold deep water, as the most promising of the ocean energy technologies. As a result, the OET Program is concentrating on research that advances the OTEC technology. The program also continues to monitor and study developments in wave energy, ocean current, and salinity gradient concepts; but it is not actively developing these technologies now.

  12. Annual Energy Review 2000

    SciTech Connect

    Seiferlein, Katherine E.

    2001-08-01

    The Annual Energy Review (AER) presents the Energy Information Administration’s historical energy statistics. For many series, statistics are given for every year from 1949 through 2000. The statistics, expressed in either physical units or British thermal units, cover all major energy activities, including consumption, production, trade, stocks, and prices, for all major energy commodities, including fossil fuels, electricity, and renewable energy sources. Publication of this report is required under Public Law 95–91 (Department of Energy Organization Act), Section 205(c), and is in keeping with responsibilities given to the Energy Information Administration under Section 205(a)(2), which states: “The Administrator shall be responsible for carrying out a central, comprehensive, and unified energy data and information program which will collect, evaluate, assemble, analyze, and disseminate data and information....” The AER is intended for use by Members of Congress, Federal and State agencies, energy analysts, and the general public. EIA welcomes suggestions from readers regarding data series in the AER and in other EIA publications.

  13. Annual Energy Review 1993

    SciTech Connect

    Not Available

    1994-07-14

    This twelfth edition of the Annual Energy Review (AER) presents the Energy Information Administration`s historical energy statistics. For most series, statistics are given for every year from 1949 through 1993. Because coverage spans four and a half decades, the statistics in this report are well-suited to long-term trend analyses. The AER is comprehensive. It covers all major energy activities, including consumption, production, trade, stocks, and prices, for all major energy commodities, including fossil fuels and electricity. The AER also presents Energy Information Administration (EIA) statistics on some renewable energy sources. EIA estimates that its consumption series include about half of the renewable energy used in the United States. For a more complete discussion of EIA`s renewables data, see p. xix, ``Introducing Expanded Coverage of Renewable Energy Data Into the Historical Consumption Series.`` Copies of the 1993 edition of the Annual Energy Review may be obtained by using the order form in the back of this publication. Most of the data in the 1993 edition also are available on personal computer diskette. For more information about the diskettes, see the back of this publication. In addition, the data are available as part of the National Economic, Social, and Environmental Data Bank on a CD-ROM. For more information about the data bank, contact the US Department of Commerce Economics and Statistics Administration, on 202-482-1986.

  14. Annual Energy Review 2006

    SciTech Connect

    Seiferlein, Katherine E.

    2007-06-01

    The Annual Energy Review (AER) is the Energy Information Administration's (EIA) primary report of annual historical energy statistics. For many series, data begin with the year 1949. Included are data on total energy production, consumption, and trade; overviews of petroleum, natural gas, coal, electricity, nuclear energy, renewable energy, international energy, as well as financial and environment indicators; and data unit conversion tables. Publication of this report is required under Public Law 95–91 (Department of Energy Organization Act), Section 205(c), and is in keeping with responsibilities given to the EIA under Section 205(a)(2), which states: “The Administrator shall be responsible for carrying out a central, comprehensive, and unified energy data and information program which will collect, evaluate, assemble, analyze, and disseminate data and information....” The AER is intended for use by Members of Congress, Federal and State agencies, energy analysts, and the general public. EIA welcomes suggestions from readers regarding data series in the AER and in other EIA publications.

  15. Annual Energy Review 2005

    SciTech Connect

    Seiferlein, Katherine E.

    2006-07-01

    The Annual Energy Review (AER) is the Energy Information Administration's (EIA) primary report of annual historical energy statistics. For many series, data begin with the year 1949. Included are data on total energy production, consumption, and trade; overviews of petroleum, natural gas, coal, electricity, nuclear energy, renewable energy, international energy, as well as financial and environment indicators; and data unit conversion tables. Publication of this report is required under Public Law 95–91 (Department of Energy Organization Act), Section 205(c), and is in keeping with responsibilities given to the EIA under Section 205(a)(2), which states: “The Administrator shall be responsible for carrying out a central, comprehensive, and unified energy data and information program which will collect, evaluate, assemble, analyze, and disseminate data and information....” The AER is intended for use by Members of Congress, Federal and State agencies, energy analysts, and the general public. EIA welcomes suggestions from readers regarding data series in the AER and in other EIA publications.

  16. Annual Energy Review 2004

    SciTech Connect

    Seiferlein, Katherine E.

    2005-08-01

    The Annual Energy Review (AER) is the Energy Information Administration's (EIA) primary report of annual historical energy statistics. For many series, data begin with the year 1949. Included are data on total energy production, consumption, and trade; overviews of petroleum, natural gas, coal, electricity, nuclear energy, renewable energy, international energy, as well as financial and environment indicators; and data unit conversion tables. Publication of this report is required under Public Law 95–91 (Department of Energy Organization Act), Section 205(c), and is in keeping with responsibilities given to the EIA under Section 205(a)(2), which states: “The Administrator shall be responsible for carrying out a central, comprehensive, and unified energy data and information program which will collect, evaluate, assemble, analyze, and disseminate data and information....” The AER is intended for use by Members of Congress, Federal and State agencies energy analysts, and the general public. EIA welcomes suggestions from readers regarding data series in the AER and in other EIA publications.

  17. Measuring Energy Sustainability

    SciTech Connect

    Greene, David L

    2009-01-01

    For the purpose of measurement, energy sustainability is defined as ensuring that future generations have energy resources that enable them to achieve a level of well-being at least as good as that of the current generation. It is recognized that there are valid, more comprehensive understandings of sustainability and that energy sustainability as defined here is only meaningful when placed in a broader context. Still, measuring energy sustainability is important to society because the rates of consumption of some fossil resources are now substantial in relation to measures of ultimate resources, and because conflicts between fossil energy use and environmental sustainability are intensifying. Starting from the definition, an equation for energy sustainability is derived that reconciles renewable fl ows and nonrenewable stocks, includes the transformation of energy into energy services, incorporates technological change and, at least notionally, allows for changes in the relationship between energy services and societal well-being. Energy sustainability must be measured retrospectively as well as prospectively, and methods for doing each are discussed. Connections to the sustainability of other resources are also critical. The framework presented is merely a starting point; much remains to be done to make it operational.

  18. Annual Energy Review 2011

    SciTech Connect

    Fichman, Barbara T.

    2012-09-01

    The Annual Energy Review (AER) is the U.S. Energy Information Administration's (EIA) primary report of annual historical energy statistics. For many series, data begin with the year 1949. Included are statistics on total energy production, consumption, trade, and energy prices; overviews of petroleum, natural gas, coal, electricity, nuclear energy, and renewable energy; financial and environment indicators; and data unit conversions. Publication of this report is required under Public Law 95–91 (Department of Energy Organization Act), Section 205(c), and is in keeping with responsibilities given to the EIA under Section 205(a)(2), which states: “The Administrator shall be responsible for carrying out a central, comprehensive, and unified energy data and information program which will collect, evaluate, assemble, analyze, and disseminate data and information....” The AER is intended for use by Members of Congress, Federal and State agencies, energy analysts, and the general public. EIA welcomes suggestions from readers regarding the content of the AER and other EIA publications.

  19. Carolinas Energy Career Center

    SciTech Connect

    Classens, Anver; Hooper, Dick; Johnson, Bruce

    2013-03-31

    Central Piedmont Community College (CPCC), located in Charlotte, North Carolina, established the Carolinas Energy Career Center (Center) - a comprehensive training entity to meet the dynamic needs of the Charlotte region's energy workforce. The Center provides training for high-demand careers in both conventional energy (fossil) and renewable energy (nuclear and solar technologies/energy efficiency). CPCC completed four tasks that will position the Center as a leading resource for energy career training in the Southeast: • Development and Pilot of a New Advanced Welding Curriculum, • Program Enhancement of Non-Destructive Examination (NDE) Technology, • Student Support through implementation of a model targeted toward Energy and STEM Careers to support student learning, • Project Management and Reporting. As a result of DOE funding support, CPCC achieved the following outcomes: • Increased capacity to serve and train students in emerging energy industry careers; • Developed new courses and curricula to support emerging energy industry careers; • Established new training/laboratory resources; • Generated a pool of highly qualified, technically skilled workers to support the growing energy industry sector.

  20. Annual Energy Review 1997

    SciTech Connect

    Seiferlein, Katherine E.

    1998-07-01

    The Annual Energy Review (AER) presents the Energy Information Administration’s historical energy statistics. For many series, statistics are given for every year from 1949 through 1997. The statistics, expressed in either physical units or British thermal units, cover all major energy activities, including consumption, production, trade, stocks, and prices, for all major energy commodities, including fossil fuels, electricity, and renewable energy sources. Publication of this report is in keeping with responsibilities given to the Energy Information Administration (EIA) in Public Law 95–91 (Department of Energy Organization Act), which states, in part, in Section 205(a)(2) that: “The Administrator shall be responsible for carrying out a central, comprehensive, and unified energy data and information program which will collect, evaluate, assemble, analyze, and disseminate data and information....” The AER is intended for use by Members of Congress, Federal and State agencies, energy analysts, and the general public. EIA welcomes suggestions from readers regarding data series in the AER and in other EIA publications.

  1. Regional Renewable Energy Cooperatives

    NASA Astrophysics Data System (ADS)

    Hazendonk, P.; Brown, M. B.; Byrne, J. M.; Harrison, T.; Mueller, R.; Peacock, K.; Usher, J.; Yalamova, R.; Kroebel, R.; Larsen, J.; McNaughton, R.

    2014-12-01

    We are building a multidisciplinary research program linking researchers in agriculture, business, earth science, engineering, humanities and social science. Our goal is to match renewable energy supply and reformed energy demands. The program will be focused on (i) understanding and modifying energy demand, (ii) design and implementation of diverse renewable energy networks. Geomatics technology will be used to map existing energy and waste flows on a neighbourhood, municipal, and regional level. Optimal sites and combinations of sites for solar and wind electrical generation (ridges, rooftops, valley walls) will be identified. Geomatics based site and grid analyses will identify best locations for energy production based on efficient production and connectivity to regional grids and transportation. Design of networks for utilization of waste streams of heat, water, animal and human waste for energy production will be investigated. Agriculture, cities and industry produce many waste streams that are not well utilized. Therefore, establishing a renewable energy resource mapping and planning program for electrical generation, waste heat and energy recovery, biomass collection, and biochar, biodiesel and syngas production is critical to regional energy optimization. Electrical storage and demand management are two priorities that will be investigated. Regional scale cooperatives may use electric vehicle batteries and innovations such as pump storage and concentrated solar molten salt heat storage for steam turbine electrical generation. Energy demand management is poorly explored in Canada and elsewhere - our homes and businesses operate on an unrestricted demand. Simple monitoring and energy demand-ranking software can easily reduce peaks demands and move lower ranked uses to non-peak periods, thereby reducing the grid size needed to meet peak demands. Peak demand strains the current energy grid capacity and often requires demand balancing projects and

  2. 77 FR 64112 - Office of Energy Efficiency and Renewable Energy

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-18

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Office of Energy Efficiency and Renewable Energy Nationwide Categorical Waivers of the American Recovery and Reinvestment Act AGENCY: Office of Energy Efficiency and Renewable Energy, U.S. Department of Energy...

  3. 78 FR 78340 - Renewable Energy and Energy Efficiency Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-26

    ... International Trade Administration Renewable Energy and Energy Efficiency Advisory Committee AGENCY... Renewable Energy and Energy Efficiency Advisory Committee (RE&EEAC) will meet via conference call on January... renewable energy and energy efficiency (RE&EE) products and services. DATES: January 23, 2014, from 2:00...

  4. 76 FR 44576 - Renewable Energy and Energy Efficiency Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-26

    ... International Trade Administration Renewable Energy and Energy Efficiency Advisory Committee AGENCY: U.S... Renewable Energy and Energy Efficiency Advisory Committee (RE&EEAC) will meet via conference call to... expand the competitiveness of the U.S. renewable energy and energy efficiency industries,...

  5. Appetite and energy balancing.

    PubMed

    Rogers, Peter J; Brunstrom, Jeffrey M

    2016-10-01

    The idea that food intake is motivated by (or in anticipation of) 'hunger' arising from energy depletion is apparent in both public and scientific discourse on eating behaviour. In contrast, our thesis is that eating is largely unrelated to short-term energy depletion. Energy requirements meal-to-meal are trivial compared with total body energy stores, and energy supply to the body's tissues is maintained if a meal or even several meals are missed. Complex and exquisite metabolic machinery ensures that this happens, but metabolic regulation is only loosely coupled with the control of energy intake. Instead, food intake needs to be controlled because the limited capacity of the gut means that processing a meal presents a significant physiological challenge and potentially hinders other activities. We illustrate the relationship between energy (food) intake and energy expenditure with a simple analogy in which: (1) water in a bathtub represents body energy content, (2) water in a saucepan represents food in the gut, and (3) the bathtub is filled via the saucepan. Furthermore, (4) it takes hours to process and pass the full energy (macronutrient) content of the saucepan to the bathtub, and (5) both the saucepan and bathtub resist filling, representing negative feedbacks on appetite (desire to eat). This model is consistent with the observations that appetite is reduced acutely by energy intake (a meal added to the limited capacity of the saucepan/gut), but not increased by an acute increase in energy expenditure (energy removed from the large store of energy in the bathtub/body). The existence of relatively very weak but chronic negative feedback on appetite proportional to body fatness is supported by observations on the dynamics of energy intake and weight gain in rat dietary obesity. (We use the term 'appetite' here because 'hunger' implies energy depletion.) In our model, appetite is motivated by the accessibility of food and the anticipated and experienced

  6. Appetite and energy balancing.

    PubMed

    Rogers, Peter J; Brunstrom, Jeffrey M

    2016-10-01

    The idea that food intake is motivated by (or in anticipation of) 'hunger' arising from energy depletion is apparent in both public and scientific discourse on eating behaviour. In contrast, our thesis is that eating is largely unrelated to short-term energy depletion. Energy requirements meal-to-meal are trivial compared with total body energy stores, and energy supply to the body's tissues is maintained if a meal or even several meals are missed. Complex and exquisite metabolic machinery ensures that this happens, but metabolic regulation is only loosely coupled with the control of energy intake. Instead, food intake needs to be controlled because the limited capacity of the gut means that processing a meal presents a significant physiological challenge and potentially hinders other activities. We illustrate the relationship between energy (food) intake and energy expenditure with a simple analogy in which: (1) water in a bathtub represents body energy content, (2) water in a saucepan represents food in the gut, and (3) the bathtub is filled via the saucepan. Furthermore, (4) it takes hours to process and pass the full energy (macronutrient) content of the saucepan to the bathtub, and (5) both the saucepan and bathtub resist filling, representing negative feedbacks on appetite (desire to eat). This model is consistent with the observations that appetite is reduced acutely by energy intake (a meal added to the limited capacity of the saucepan/gut), but not increased by an acute increase in energy expenditure (energy removed from the large store of energy in the bathtub/body). The existence of relatively very weak but chronic negative feedback on appetite proportional to body fatness is supported by observations on the dynamics of energy intake and weight gain in rat dietary obesity. (We use the term 'appetite' here because 'hunger' implies energy depletion.) In our model, appetite is motivated by the accessibility of food and the anticipated and experienced

  7. Energy Problems and Environmental Concern

    ERIC Educational Resources Information Center

    Train, Russell E.

    1973-01-01

    Discusses problems encountered in energy extraction and consumption, involving nuclear power plant construction, environmental consequences of energy systems, and energy conservation ethics. Indicates that the increasing concern over environmental quality is not the true cause of present energy problems. (CC)

  8. Tomorrow`s energy today

    SciTech Connect

    Not Available

    1994-04-01

    This book presents the 50 award-winning projects in energy efficiency and renewable energy technologies that were selected for the Department`s 1994 National Awards Program for Energy Efficiency and Renewable Energy.

  9. Comparison of morphology evolution of Ge(001) homoepitaxial films grown by pulsed laser deposition and molecular-beam epitaxy

    SciTech Connect

    Shin Byungha; Leonard, John P.; McCamy, James W.; Aziz, Michael J.

    2005-10-31

    Using a dual molecular-beam epitaxy (MBE)-pulsed laser deposition (PLD) ultrahigh vacuum chamber, we have conducted the first experiments under identical thermal, background, and surface preparation conditions to compare Ge(001) homoepitaxial growth morphology in PLD and MBE. We find that in PLD with low kinetic energy and in MBE the film morphology evolves in a similar fashion: initially irregularly shaped mounds form, followed by pyramidal mounds with edges of the square-base along the <100> directions; the film roughness and mound separation increase with film thickness. In PLD with high kinetic energy, well-defined pyramidal mounds are not observed and the morphology rather resembles that of an ion-etched Ge(001) surface. The areal feature density is higher for PLD films than for MBE films grown at the same average growth rate and temperature. Furthermore, the dependence upon film thickness of roughness and feature separation differ for PLD and MBE. We attribute these differences to the higher yield of defect generation by energetic species in PLD.

  10. Monthly energy review, May 1995

    SciTech Connect

    1995-05-24

    Energy production during Feb 95 totaled 5.4 quadrillion Btu (Q), 3.1% over Feb 94. Energy consumption totaled 7.4 Q, 0.7% below Feb 94. Net imports of energy totaled 1.3 Q, 5.6% below Feb 94. This publication is divided into energy overview, energy consumption, petroleum, natural gas, oil and gas resource development, coal, electricity, nuclear energy, energy prices, and international energy.

  11. Renewable energy development in China

    SciTech Connect

    Junfeng, Li

    1996-12-31

    This paper presents the resources availability, technologies development and their costs of renewable energies in China and introduces the programs of renewable energies technologies development and their adaptation for rural economic development in China. As the conclusion of this paper, renewable energies technologies are suitable for some rural areas, especially in the remote areas for both household energy and business activities energy demand. The paper looks at issues involving hydropower, wind energy, biomass combustion, geothermal energy, and solar energy.

  12. Monthly energy review, March 1997

    SciTech Connect

    1997-03-01

    This is an overview of the March 1997 energy statistics by the Energy Information Administration. The Contents of the report include an update on the effects of Title IV of the Clean Air Act Amendments of 1990 on electric utilities, an energy overview, US energy production, energy consumption, trade stocks and prices for petroleum, natural gas, oil and gas resource development, coal, electricity, nuclear energy, energy prices, and international energy. 37 figs., 60 tabs.

  13. The Flow of Energy

    NASA Astrophysics Data System (ADS)

    Znidarsic, F.; Robertson, G. A.

    In this paper, the flow of energy in materials is presented as mechanical waves with a distinct velocity or speed of transition. This speed of transition came about through the observations of cold fusion experiments, i.e., Low Energy Nuclear Reactions (LENR) and superconductor gravity experiments, both assumed speculative by mainstream science. In consideration of superconductor junctions, the LENR experiments have a similar speed of transition, which seems to imply that the reactions in the LENR experiment are discrete quantized reactions (energy - burst vs. continuous). Here an attempt is made to quantify this new condition as it applies to electrons; toward the progression of quantized energy flows (discrete energy burst) as a new source of clean energy and force mechanisms (i.e, propulsion).

  14. Annual energy review 1994

    NASA Astrophysics Data System (ADS)

    1995-07-01

    This 13th edition presents the Energy Information Administration's historical energy statistics. For most series, statistics are given for every year from 1949 through 1994; thus, this report is well-suited to long-term trend analyses. It covers all major energy activities, including consumption, production, trade, stocks, and prices for all major energy commodities, including fossil fuels and electricity. Statistics on renewable energy sources are also included: this year, for the first time, usage of renewables by other consumers as well as by electric utilities is included. Also new is a two-part, comprehensive presentation of data on petroleum products supplied by sector for 1949 through 1994. Data from electric utilities and nonutilities are integrated as 'electric power industry' data; nonutility power gross generation are presented for the first time. One section presents international statistics (for more detail see EIA's International Energy Annual).

  15. Energy: An annotated bibliography

    NASA Technical Reports Server (NTRS)

    Blow, S. J. (Compiler)

    1975-01-01

    This bibliography is the first update of a previous energy bibliography dated August 1974. It contains approximately 3,300 selected references on energy and energy related topics from bibliographic sources dated August 1974 through December 1974. The references are arranged by date, with the latest works first, in subject categories. (1) Energy and power - general; resources, supply/demand, and forecasting; policy, legislation, and regulation; research and development, environment; consumption and economics; conservation; and systems analysis. (2) Energy and power sources - general; fossil fuels; hydrogen and other fuels; organic wastes and waste heat; nuclear; geothermal; solar; wind; ocean/water; magnetohydrodynamics and electrohydrodynamics; and gas and steam turbines. (3) Energy and power storage and transmission.

  16. Annual energy review 1994

    SciTech Connect

    1995-07-01

    This 13th edition presents the Energy Information Administration`s historical energy statistics. For most series, statistics are given for every year from 1949 through 1994; thus, this report is well-suited to long-term trend analyses. It covers all major energy activities, including consumption, production, trade, stocks, and prices for all major energy commodities, including fossil fuels and electricity. Statistics on renewable energy sources are also included: this year, for the first time, usage of renewables by other consumers as well as by electric utilities is included. Also new is a two-part, comprehensive presentation of data on petroleum products supplied by sector for 1949 through 1994. Data from electric utilities and nonutilities are integrated as ``electric power industry`` data; nonutility power gross generation are presented for the first time. One section presents international statistics (for more detail see EIA`s International Energy Annual).

  17. Solar energy modulator

    NASA Technical Reports Server (NTRS)

    Hale, R. R. (Inventor); Mcdougal, A. R.

    1984-01-01

    A module is described with a receiver having a solar energy acceptance opening and supported by a mounting ring along the optic axis of a parabolic mirror in coaxial alignment for receiving solar energy from the mirror, and a solar flux modulator plate for varying the quantity of solar energy flux received by the acceptance opening of the module. The modulator plate is characterized by an annular, plate-like body, the internal diameter of which is equal to or slightly greater than the diameter of the solar energy acceptance opening of the receiver. Slave cylinders are connected to the modulator plate for supporting the plate for axial displacement along the axis of the mirror, therby shading the opening with respect to solar energy flux reflected from the surface of the mirror to the solar energy acceptance opening.

  18. Energy and human health.

    PubMed

    Smith, Kirk R; Frumkin, Howard; Balakrishnan, Kalpana; Butler, Colin D; Chafe, Zoë A; Fairlie, Ian; Kinney, Patrick; Kjellstrom, Tord; Mauzerall, Denise L; McKone, Thomas E; McMichael, Anthony J; Schneider, Mycle

    2013-01-01

    Energy use is central to human society and provides many health benefits. But each source of energy entails some health risks. This article reviews the health impacts of each major source of energy, focusing on those with major implications for the burden of disease globally. The biggest health impacts accrue to the harvesting and burning of solid fuels, coal and biomass, mainly in the form of occupational health risks and household and general ambient air pollution. Lack of access to clean fuels and electricity in the world's poor households is a particularly serious risk for health. Although energy efficiency brings many benefits, it also entails some health risks, as do renewable energy systems, if not managed carefully. We do not review health impacts of climate change itself, which are due mostly to climate-altering pollutants from energy systems, but do discuss the potential for achieving near-term health cobenefits by reducing certain climate-related emissions.

  19. Energy Organizational Planning

    SciTech Connect

    Gina C. Paradis; James Yockey; Tracey LeBeau

    2009-04-17

    As the Seneca Nation of Indians (SNI) continues to refine and finalize its Strategic Energy Plan, it became necessary to insure that a sustainable organization structure was developed through which the energy program and its initiatives could be nurtured and managed. To that end, SNI undertook a study to thoroughly evaluate the existing organizational structures and assess the requisite changes and/or additions to that framework that would complement the mission of the Strategic Plan. The goal of this study was to analyze, work with staff and leadership and recommend the most effective plan for the development of an organizational framework within which the Seneca could more effectively exercise energy sovereignty – control and manage their natural resource assets – i.e. develop its own energy resources, meet the current and projected energy needs of their community, and “sit at the table” with other regional energy providers to deal with issues on a peer-to-peer basis.

  20. Energy spectra of high energy atmospheric neutrinos

    NASA Technical Reports Server (NTRS)

    Mitsui, K.; Minorikawa, Y.

    1985-01-01

    Focusing on high energy neutrinos ( or = 1 TeV), a new calculation of atmospheric neutrino intensities was carried out taking into account EMC effects observed in P-A collisions by accelerator, recent measurement of primary cosmic ray spectrum and results of cosmic ray muon spectrum and charge ratio. Other features of the present calculation are (1) taking into account kinematics of three body decays of kaons and charm particles in diffusion equations and (2) taking into account energy dependence of kaon production.